JPH10232584A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent lowering of an image quality caused by resonance of a photoreceptor drum and the structure on the periphery butting to the photoreceptor drum, oriented from stick-slip of a cleaning blade becoming to a vibration exciting source of the wide range noise. SOLUTION: This image forming device is provided with several sliding member 81 and 82 fitted internally or externally contact with the photoreceptor drum 1 so as to be rotated with the photoreceptor drum 1, in the case the vibration oriented from the wide range noise is about to occur on the photoreceptor drum 1, for instance, due to the stick-slip of the cleaning blade 71, the several sliding member 81 and 82 is made possible to apply the rolling friction on the internal or external periphery held in contact therewith while being rotated with the rotating photoreceptor drum 1, therefore the vibration oriented from the wide range noise is allowed to attenuate, and the abnormal noise being caused by making the surface of the photoreceptor drum 1 as the noise radiation plane and the resonance of the photoreceptor 1 and the structure on the periphery held in contact with the photoreceptor 1 is severally restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a laser printer and an electronic copier, and more particularly to a method for reducing noise and preventing image quality deterioration due to vibration of a photosensitive drum.

[0002]

2. Description of the Related Art In a copying machine using an electrophotographic system, a photosensitive drum is used as a printing medium. In this photosensitive drum, a photoconductor is applied to an outer peripheral surface of a cylindrical drum formed of a conductor such as aluminum. The uniformly charged photoconductor on the surface of the photoconductor drum causes a change in physical properties by light including image information sent from the optical writing system, thereby forming an electrostatic latent image on the photoconductor drum surface. The formed electrostatic latent image is visualized by toner as a developer and transferred to a recording sheet to form an image.
The toner remaining on the photosensitive drum after transferring the image is scraped off by the cleaning blade and removed.

As described above, in order to remove the developer remaining on the photosensitive drum at the time of image formation, the remaining developer is scraped off by a cleaning blade in contact with the photosensitive drum. Abnormal noise was generated due to the frictional force generated between the blade and the blade.
Therefore, an image forming apparatus for reducing noise generated when removing the developer remaining on the photosensitive drum is disclosed in, for example, JP-A-63-271388 and JP-A-64-7089. ing. In these image forming apparatuses, abnormal noise generated in a cleaning process during image formation is caused by self-excited vibration of the photosensitive drum due to frictional force generated between the photosensitive drum and the cleaning blade. Ascertain that the sound is in the audible frequency band of 10.65 KHz, and insert foamed polyurethane or the like, which is a vibration damping member formed inside the photosensitive drum so as to contact the inner wall surface of the photosensitive drum, inside the photosensitive drum or Elastic press fit. This vibration damping member attenuates the vibration generated on the photosensitive drum, thereby preventing the occurrence of abnormal noise of 10.65 KHz.

[0004]

One of the factors inhibiting high image quality in an electrophotographic copying machine or the like is a phenomenon called jitter or banding. In particular, when the improvement of image quality is promoted by the introduction of digital technology, the writing of laser beam
The positional accuracy for each line is strictly required, and it is necessary to accurately drive the photosensitive drum, which is one of the factors that control the positional accuracy, in order to form a high-quality image.

Further, when the cleaning blade frictionally slides on the photosensitive drum at the time of image formation, and the frictional sliding has a negative coefficient of kinetic friction coefficient with respect to the sliding speed, the cleaning blade is driven by the photosensitive blade. Chattering, that is, the phenomenon of stick-slip due to repeated contact with or separation from the contact surface of the drum occurs. The stick-slip generated by the cleaning blade serves as a vibration source of noise called white noise or broadband noise having uniform energy in a physically wide frequency band, and the photosensitive drum and surrounding structures in contact with the photosensitive drum. Or a certain frequency component in the broadband noise is transmitted to the surface and the inner periphery of the photoconductor drum, and the surface of the photoconductor drum is used as an acoustic radiation surface to generate a tactile noise.

However, as shown in JP-A-63-271388 and JP-A-64-7089, abnormal noise having a single frequency of 10.65 KHz generated from a photosensitive drum in a cleaning process is not considered. Although the noise was eliminated by the vibration damping member, the broadband noise generated by the cleaning blade stick-slip was not eliminated, so the generated broadband noise resonated the photosensitive drum and the surrounding structures that contacted the photosensitive drum. By doing so, for example, the rotation speed of the photosensitive drum fluctuates, and writing with a laser beam may be disturbed, which may cause deterioration in image quality.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned disadvantages, and attenuates broadband noise generated on a photosensitive drum, thereby preventing abnormal noise generated on the surface of the photosensitive drum as an acoustic radiation surface and preventing photosensitive noise. It is an object of the present invention to provide an image forming apparatus which prevents a deterioration in image quality due to resonance of a structure around a body drum and a photosensitive drum and resonates with the photosensitive drum, thereby achieving high image quality and low noise.

[0008]

An image forming apparatus according to the present invention is a photosensitive drum comprising a cylindrical drum made of a conductor having a photoconductor coated on the surface thereof and flanges attached to both ends of the cylindrical drum. The image forming apparatus according to claim 1, further comprising a sliding member that circumscribes or inscribes the photosensitive drum to apply rolling friction.

A second image forming apparatus according to the present invention comprises: a cylindrical drum made of a conductor having a photoconductor coated on its surface;
In an image forming apparatus having a photosensitive drum composed of flanges attached to both ends of a cylindrical drum, a rolling friction is added between a transfer unit and a charging unit, which are disposed with a cleaning unit interposed, by circumscribing the photosensitive drum. It is characterized by having a sliding member that performs.

A third image forming apparatus according to the present invention comprises: a cylindrical drum made of a conductor having a photoconductor coated on its surface;
In an image forming apparatus having a photosensitive drum including flanges attached to both ends of a cylindrical drum, a sliding member that moves in contact with the photosensitive drum and moves along the inner peripheral surface to add rolling friction It is characterized by having.

It is desirable that the sliding member has a roller shape.

A fourth image forming apparatus according to the present invention comprises a cylindrical drum made of a conductor having a photoconductor coated on the surface thereof;
In an image forming apparatus having a photosensitive drum including a flange attached to both ends of a cylindrical drum, a granular sliding member that moves along the inner peripheral surface of the photosensitive drum is provided.

A fifth image forming apparatus according to the present invention comprises a polymer layer having a high attenuation rate formed on the outer peripheral surface of a cylindrical drum made of a conductor, and a photoconductor layer applied on the surface of the polymer layer. Characterized in that it has a photosensitive drum.

According to a sixth aspect of the present invention, there is provided an image forming apparatus comprising: a polymer layer having a high attenuation rate formed on an inner peripheral surface of a cylindrical drum made of a conductor; and a photoconductor layer coated on an outer peripheral surface of the cylindrical drum. And a photosensitive drum comprising:

It is preferable that the polymer layer is formed of rubber.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming apparatus according to the present invention comprises a cylindrical drum formed by applying a photoconductor to an outer peripheral surface of a conductor such as aluminum, and flanges attached to both ends of the cylindrical drum. And a sliding member attached to or in contact with the photosensitive drum so as to rotate with the photosensitive drum rotating about a core bar made of, for example, metal. And, when vibration due to broadband noise is about to occur on the photosensitive drum due to, for example, stick-slip of the cleaning blade, the sliding member moves from the surface inscribed or circumscribed to the photosensitive drum while rotating along with the rotating photosensitive drum. By adding rolling friction, vibration due to broadband noise is attenuated. This allows
The present invention prevents abnormal noise generated by using the surface of the photoconductor drum as an acoustic radiation surface and also prevents resonance between the photoconductor drum and surrounding structures in contact with the photoconductor drum.

Further, by making the above-mentioned sliding member into a roller shape and enlarging the contact surface of the rolling friction applied to the contact surface in or out of contact with the photosensitive drum, the vibration generated on the photosensitive drum can be quickly reduced. Attenuate.

Also, a sliding member is provided between the transfer unit and the charging unit, which are disposed with a cleaning blade therebetween along the rotation direction of the photosensitive drum, so as to circumscribe the photosensitive drum and rotate therewith. The vibration generated on the photosensitive drum can be quickly attenuated by the rolling friction without impairing the cleaning performance of the toner remaining on the photosensitive drum.

In the above description, when the sliding member is disposed so as to be in or out of contact with the photosensitive drum, for example, the sliding member is fixed so as to rotate with the photosensitive drum around a core rod made of metal or the like. The member may be attached so as to be brought into contact with the photosensitive drum and to move along the inner peripheral surface. In this case, since the sliding member is not fixed, for example, when the rotation of the photosensitive drum rises or decelerates, the sliding member undergoes a reverse change due to its own inertial force. As a result, the rolling friction of the sliding member increases, and in addition to the vibration caused by the broadband noise generated on the photoconductor drum due to the sticking of the cleaning blade, the rotation of the photoconductor drum varies at the time of rising or deceleration. Vibration can be quickly dissipated.

Further, in the above, the use of the sliding member for adding the rolling friction makes it possible to reduce the vibration caused by the broadband noise generated on the photosensitive drum and the vibration caused by the rise or the deceleration of the rotation of the photosensitive drum. Although it is attenuated, a granular sliding member that moves along the inner peripheral surface of the photosensitive drum may be used. In this case, the granular sliding member rolls and disperses along with the rotation of the photosensitive drum along the inner periphery of the photosensitive drum and moves while dispersing. In addition to the frictional damping of the vibration generated by the addition of vibration, the vibration transmitted from the inner peripheral surface of the contacting photosensitive drum is attenuated by the hysteresis due to the material characteristics of the granular sliding member. This reliably and quickly attenuates the vibration caused by the broadband noise generated on the photosensitive drum due to the stick slip of the cleaning blade, and the vibration caused by the fluctuation at the time of rising or deceleration of the rotation of the photosensitive drum.

In the above, the vibration generated on the photosensitive drum is attenuated by using the sliding member in contact with the photosensitive drum, but the vibration generated on the photosensitive drum is attenuated without using the sliding member. can do. In this case, the photosensitive drum includes a polymer layer having a high attenuation rate formed on the outer peripheral surface of a cylindrical drum made of a conductor such as aluminum, and a photoconductor layer applied to the surface of the polymer layer.
The polymer layer having a high damping rate has a hysteresis attenuation due to the material properties of the polymer layer when the vibration transmitted by the photoconductor layer is generated, for example, when vibration due to broadband noise occurs due to stick-slip of the cleaning blade. I do. Thus, the vibration transmitted to the cylindrical drum is shut off, and the vibration generated on the photosensitive drum is quickly dissipated.

In the above-described photosensitive drum, a polymer layer having a high attenuation rate is formed between the cylindrical drum and the photoconductor layer. The photoconductor layer is applied to the outer peripheral surface of the cylindrical drum. ,
A polymer layer having a high attenuation rate may be formed on the inner peripheral surface of the cylindrical drum. In this case, the polymer layer having a high attenuation rate formed on the inner peripheral surface of the cylindrical drum has vibration caused by broadband noise transmitted through the cylindrical drum, for example, caused by stick-slip of the cleaning blade. Hysteresis attenuates due to material properties. As a result, the vibration generated on the photosensitive drum is quickly dissipated.

Further, by using a material having a low molecular-level bonding force, such as a flowing rubber, a natural rubber, a silicone rubber, or a gel, as a material for forming the polymer layer, vibration transmitted to the polymer layer can be accelerated. Hysteresis can be attenuated.

[0024]

FIG. 1 is a block diagram of an image forming section of an electrophotographic copying machine according to one embodiment of the present invention. As shown in the figure, the image forming section includes a photosensitive drum 1, a charging unit 2, an exposure unit 3, a developing unit 4, a transfer unit 5, and a peeling unit 6 which are arranged around the photosensitive drum 1 along the rotation direction.
And a cleaning unit 7 and sliding members 81 and 82. Then, the photosensitive drum 1 charged by the charging unit 2 is exposed by the exposure unit 3 to form an electrostatic latent image, and toner is adhered to the formed electrostatic latent image by the developing unit 4 to form a toner image. Transfer unit 5 formed toner image
Then, the recording paper on which the toner image has been transferred is transferred to the recording paper conveyed by the registration roller 9, separated from the photosensitive drum by the separation unit 6, sent to a fixing unit (not shown) by the paper conveyance unit 10 and fixed. On the other hand, the toner remaining on the photosensitive drum 1 is scraped off by the cleaning blade 71 of the cleaning unit 7 and removed.

The photosensitive drum 1 is composed of a cylindrical drum 12 made of a conductor such as aluminum coated with a photoconductive layer 11 on its surface, and flanges (not shown) attached to both ends of the cylindrical drum 12. , And is rotated by a driving mechanism (not shown) having a drum motor, a gear, and the like. The rotation of the photosensitive drum 1 causes the cleaning blade 71 to frictionally slide with respect to the photosensitive drum 1. When the kinetic friction coefficient has a negative gradient with respect to the sliding speed during the friction sliding, the cleaning blade 71 performs cleaning. The blade 71 generates a phenomenon called stick-slip. This stick slip is microscopically caused by the photosensitive drum 1 and the cleaning blade 71.
And the friction when the projections on each surface get over each other. The sliding friction becomes a vibration source of noise called white noise or broadband noise having uniform energy in a physically wide frequency band, and resonates the photosensitive drum 1 and a surrounding structure in contact with the photosensitive drum 1. Alternatively, a certain frequency component in the broadband noise is transmitted to the surface and the inner periphery of the photosensitive drum 1, and the surface of the photosensitive drum 1 is used as an acoustic radiation surface to generate a tactile noise.

The sliding members 81 and 82 are formed in a spherical, polygonal or roller shape using a material such as metal, plastic or rubber. The holding method is not particularly limited. For example, a core rod made of metal or the like may be used. It is attached to or in contact with the photosensitive drum 1 so as to rotate with the photosensitive drum 1 rotating about a shaft. When vibration due to broadband noise is about to occur on the photosensitive drum 1 due to the stick slip of the cleaning blade 71, the vibration caused by broadband noise is caused to follow the rotating photosensitive drum 1 on the surface inscribed or circumscribed. Decays due to rolling friction.

The damping due to the rolling friction uses a so-called friction damping in which the vibration energy, which is an external force, is converted into heat and damped by the friction between the structures in contact with each other. As shown in the envelope characteristic diagram of FIG.
When the horizontal axis is time T and the vertical axis is vibration amplitude lnX, which is an external force, the vibration amplitude, which is an external force, attenuates slightly with the passage of time. Generally, the frictional force between structures is almost constant. In this case, in one cycle of the vibration, which is an external force, frictional energy of about twice the amplitude H is dissipated and the vibration, which is an external force, is attenuated. In other words, the damping due to the rolling friction in the sliding members 81 and 82 is such that the surface where the friction damping occurs is rotated by rotating with the photosensitive drum 1 to maintain a stable frictional state. By adding to 1, vibration caused by broadband noise occurring on the photosensitive drum 1 due to the sticking of the cleaning blade 71 is attenuated.

In this manner, rolling friction attenuation is applied to the photosensitive drum 1 by the sliding member 8 in or out of contact with the photosensitive drum 1, and vibration caused by broadband noise generated on the photosensitive drum 1 is attenuated. As a result, it is possible to prevent abnormal noise generated by using the surface of the photosensitive drum 1 as an acoustic radiation surface, and to prevent resonance between the photosensitive drum 1 and surrounding structures in contact with the photosensitive drum 1.

The friction damping includes damping due to sliding friction in addition to damping due to rolling friction. This sliding friction is the friction that occurs when the other structure slides on the surface of the structure without rolling, and absorbs vibrations, which are external forces, converts to heat and dissipates faster than rolling friction. Is high, but the frictional force increases with it.
Cleaning blade 7 tends to be unstable in frictional state
As described in 1, stick-slip could become a source of vibration and was not employed. In addition to the friction damping, there is a so-called hysteresis damping. In this hysteresis damping, the vibration amplitude, which is an external force, similarly to friction damping, attenuates slightly with the passage of time. However, as shown in the characteristic diagram of the internal loss in FIG. Assuming that the displacement X of the structure to which the vibration amplitude F is transmitted to the axis is a characteristic in which the displacement X does not simply increase in proportion to the vibration amplitude F as shown by a broken line, an elliptical hysteresis loop is formed. . The area of this ellipse corresponds to the internal loss energy, and shows that the vibrational energy, which is the external force transmitted to the inside of the structure, is attenuated by being converted into heat by the molecular level friction of the material forming the structure, that is, internal loss I have. Further, since this internal loss is determined by friction at the molecular level of the material, for example, a polymer material having a small molecular bonding force generally has a large internal loss and a large elliptical area, and a metal having a large molecular bonding force, for example, a metal, has an internal loss. The loss is small and the elliptical area is narrow. That is, as the molecular bonding force becomes smaller and the internal loss becomes larger, the convergence time of the vibration shown in the envelope characteristic of FIG. 2 becomes shorter. In addition, when the damping rate of frictional damping and hysteresis damping are compared using a metal for the structure, friction damping is several percent, and hysteresis damping is a comma several percent, and generally, friction damping has a shorter convergence time of vibration.

Further, the sliding members 81 and 82 are formed in a roller shape, and the contact force of the rolling friction applied in contact with or in contact with the photosensitive drum 1 is increased to increase the frictional force and shorten the vibration convergence time. can do. Note that the softer the material of the roller-shaped sliding members 81 and 82, the larger the contact surface can be, which is desirable.

In this way, by making the sliding member 8 in the form of a roller, the contact surface of the rolling friction applied in contact with or in contact with the photosensitive drum 1 is increased to increase the frictional force. Vibration generated on the drum 1 can be rapidly attenuated.

In the above, the operation when the sliding members 81 and 82 are disposed in or out of contact with the rotating photosensitive drum 1 has been described, but is shown in FIG. The sliding members 81 and 82 are provided between the transfer unit 5 and the charging unit 2, which are arranged so as to sandwich the cleaning blade 71 along the rotation direction of the photosensitive drum 1 so as to be in contact with the photosensitive drum 1 and rotate therewith. Thus, the vibration generated on the photosensitive drum 1 can be attenuated by the rolling friction without impairing the cleaning performance of the toner remaining on the photosensitive drum 1. That is, when the sliding portion 81 is provided between the transfer unit 5 and the cleaning blade 71, the toner remaining on the photosensitive drum 1 adheres to the sliding portion 81, but the remaining cleaning blade 71 The cleaning performance is not impaired because the used toner is cleaned. Further, a sliding portion 82 is provided between the cleaning blade 71 and the charging unit 2.
Is provided, the cleaning blade 71 has already removed the toner remaining on the photosensitive drum 1, so that the cleaning performance can be maintained.

Thus, the cleaning blade 7
Since a sliding member 8 is arranged between the transfer unit 5 and the charging unit 2 which sandwich the photosensitive drum 1 so as to add rolling friction to the photosensitive drum 1, cleaning performance of toner remaining on the photosensitive drum 1 is improved. Can be quickly attenuated without damaging the photosensitive drum 1.

In the above description, when the sliding member 8 is arranged so as to be in or out of contact with the photosensitive drum 1, the sliding member 8 is fixed so as to rotate with the photosensitive drum 1 around a core rod made of, for example, metal. However, by attaching the sliding member 8 so as to be able to move in contact with the photosensitive drum 1 and move along the inner peripheral surface, the frictional force of the rolling friction of the sliding member 8 is increased, and the convergence time of vibration is increased. Can be faster. In this case, as shown in FIG. 5A, for example, a support member 83 movably connected to the rotation axis of the photosensitive drum 1 along the inner peripheral surface of the photosensitive drum 1, and The sliding member 8 has a sliding member 8 held by a supporting member 83 so as to be in contact with the inner peripheral surface and rotate therewith. As a result, for example, when the rotation of the photosensitive drum 1 fluctuates at the time of rising or deceleration, the reverse variations R and F with respect to the fluctuation occur due to the inertial force of the sliding member 8. As a result, the frictional force of the rolling friction by the sliding member 8 increases, and in addition to the vibration caused by the broadband noise generated on the photosensitive drum 1 due to the sticking of the cleaning blade 71, the rising of the rotation of the photosensitive drum 1 Vibration due to fluctuations during time or deceleration can be dissipated faster. Further, as shown in FIG. 5B, the sliding member 8 composed of a rotating body formed so as to be in contact with the photosensitive drum 1 and roll along the inner peripheral surface is not restrained from the photosensitive drum 1 at all. It may be arranged.

As described above, the sliding member 8 is in contact with the photosensitive drum 1 and moves along the inner peripheral surface thereof, and moves along the inner peripheral surface so that the frictional force of the rolling friction applied to the photosensitive drum 1 is increased. Therefore, vibration due to broadband noise generated on the photosensitive drum 1 and vibration due to fluctuation at the time of rising or deceleration of the rotation of the photosensitive drum can be rapidly attenuated.

In the above description, the sliding member 8 for adding rolling friction
Of the vibration caused by the broadband noise generated on the photosensitive drum 1 due to the stick slip of the cleaning blade 71, and the operation of attenuating the vibration caused by the fluctuation at the time of rising or deceleration of the rotation of the photosensitive drum 1. However, in addition to adding the rolling friction to the photosensitive drum 1, the vibration generated by adding the sliding friction is frictionally attenuated, and the transmitted vibration is further attenuated by the hysteresis, whereby the convergence time of the vibration can be further shortened. . In this case, as shown in FIG. 6, a granular sliding member 84 made of, for example, sand, powder, plastic sphere, or the like is provided on the inner peripheral surface of the photosensitive drum 1. The granular sliding member 84 moves while rolling and dispersing along with the rotation of the photoconductor drum 1 along the inner circumference of the photoconductor drum 1, and the inner peripheral surface of the photoconductor drum 1 in wide contact by being dispersed. In addition to applying rolling friction and sliding friction to frictionally attenuate vibrations generated on the photosensitive drum, the vibrations transmitted from the photosensitive drum 1 to the granular sliding member 84 are attenuated in a hysteresis manner. As a result, the granular sliding member 84 vibrates due to broadband noise generated on the photosensitive drum 1 due to the stick slip of the cleaning blade 71, and vibration due to fluctuation at the time of rising or deceleration of the rotation of the photosensitive drum 1. Can be quickly dissipated. At this time, stick-slip which is a problem due to sliding friction caused by the granular sliding member 84 does not occur. The reason is that in order to generate stick-slip, it is necessary to have an appropriate mass and elasticity.
No. 4 has no elasticity. Since the hysteresis friction attenuates the vibration energy, which is the external force transmitted into the structure, by converting it into heat by the friction at the molecular level of the material forming the structure, the material of the granular sliding member 84 is molecular. A soft material such as polyurethane, epoxy, or rubber having a small bonding force is preferable, but a hard material such as acrylic can also obtain the effect. Also, the photosensitive drum 1
Is provided with a partition inside, and the granular sliding member 8 is provided in the partition.
4 may be provided.

In this manner, the sliding friction and sliding on the inner peripheral surface of the photosensitive drum 1 are caused by the granular sliding member 84 that moves along the inner peripheral surface while rolling and dispersing in accordance with the rotation of the photosensitive drum 1. In addition to attenuating the vibration generated by adding friction, the vibration transmitted to the granular sliding member 84 is attenuated in a hysteresis manner. Vibration due to fluctuations at the time of rising or deceleration of the rotation of the drum can be reliably and quickly damped.

In the above description, the vibration generated on the photosensitive drum 1 is attenuated by using the sliding member 8 in contact with the photosensitive drum 1. The impending vibration can be attenuated. In this case, the photosensitive drum 1 is the photosensitive drum 1 shown in FIG.
As shown in an enlarged cross-sectional view of FIG. 1, a polymer layer 13 having a high attenuation rate formed on an outer peripheral surface of a cylindrical drum 12 formed of a conductor such as aluminum, and a photoconductive layer applied on the surface of the polymer layer 13. It consists of a body layer 11. For example, when the cleaning blade 71 sticks and slips to generate vibration due to broadband noise, the high-decay polymer layer 13 attenuates the vibration transmitted to the inside of the polymer layer 13 via the photoconductor 11 with hysteresis attenuation. And a cylindrical drum 1
The vibration transmitted to 2 is cut off. It should be noted that the larger the internal loss of the hysteresis attenuation, the shorter the convergence time of the vibration, so that the polymer layer 13 is preferably thick.

As described above, the polymer layer 13 having a high damping rate is formed between the cylindrical drum 12 and the photoconductor layer 11 so that the vibration transmitted to the polymer layer 13 is attenuated in a hysteresis manner. Vibration transmitted to the cylindrical drum 12 can be blocked to prevent the photosensitive drum 1 from generating vibration.

In the above description, the polymer layer 13 having a high attenuation rate is formed between the cylindrical drum 12 and the photoconductor layer 11, but as shown in FIG. The photoconductor layer 11 may be applied to the inner surface of the cylindrical drum 12 to form a polymer layer 13 having a high attenuation rate. At this time, the bonding surface between the polymer layer 13 and the cylindrical drum 12 needs to be in close contact with each other, but any method of mounting, such as bonding, welding, or press fitting, may be used. It may be interposed. As a result, the high-damping polymer layer 13 provided on the inner peripheral surface of the cylindrical drum 12 is vibrated by broadband noise generated by, for example, stick slipping of the cleaning blade 71 transmitted through the cylindrical drum 12. Is attenuated with hysteresis.

In this manner, the polymer layer 13 having a high attenuation rate is formed on the inner peripheral surface of the cylindrical drum 12, and the polymer layer 1 is formed.
Since the vibration transmitted to the photosensitive drum 3 is attenuated by hysteresis, it is possible to prevent the photosensitive drum 1 from generating vibration.

Since the polymer layer 13 attenuates the vibration generated in the photosensitive drum 1 by using hysteresis attenuation, the polymer layer 13 has a weak bonding force at the molecular level as a material for forming the polymer layer 13, for example, a flowing rubber. By using natural rubber, silicone rubber, gel, or the like, the internal loss of hysteresis attenuation can be increased and the convergence time of vibration can be shortened.

As described above, since the internal loss of the hysteresis attenuation is increased by using rubber or the like having a low molecular-level bonding force as the material of the polymer layer 13, the photosensitive drum 1
Can be attenuated more quickly.

[0044]

As described above, according to the present invention, the rolling friction is applied to the photosensitive drum by the sliding member in or out of contact with the photosensitive drum, and the vibration due to the broadband noise generated on the photosensitive drum is reduced. The attenuator prevents abnormal noise that occurs on the surface of the photosensitive drum as an acoustic radiation surface, and also prevents deterioration of image quality due to resonance of the photosensitive drum and surrounding structures that contact the photosensitive drum. High image quality and low noise can be achieved.

Further, since a sliding member is arranged between the transfer unit and the charging unit which are arranged with the cleaning blade interposed therebetween to add rolling friction to the photosensitive drum, the toner remaining on the photosensitive drum is The image quality and noise of the apparatus can be reduced without impairing the cleaning performance of the apparatus.

Further, since the sliding member is in contact with the photosensitive drum and follows the photosensitive drum and moves along the inner peripheral surface, the frictional force of the rolling friction applied to the photosensitive drum is increased. The vibration caused by the broadband noise and the vibration caused by the rise or deceleration of the rotation of the photosensitive drum can be rapidly attenuated, and the image quality and noise of the apparatus can be improved.

Further, by making the sliding member in a roller shape, the contact surface of the rolling friction to be added in or out of contact with the photosensitive drum is increased to increase the frictional force. The applied vibration can be quickly attenuated, and the image quality and noise of the apparatus can be further reduced.

Further, rolling friction and sliding friction are added to the inner peripheral surface of the photosensitive drum by a granular sliding member that moves along the inner peripheral surface while rolling and dispersing in accordance with the rotation of the photosensitive drum. In addition to frictionally damping the generated vibration,
The vibration transmitted to the granular sliding member is attenuated with hysteresis, so the vibration caused by the broadband noise generated on the photoconductor drum and the vibration caused by fluctuations at the time of rising or deceleration of the rotation of the photoconductor drum are quickly attenuated. Can be
High image quality and low noise of the device can be reliably achieved.
In addition, the manufacturing process only needs to provide an inexpensive material, which is a granular sliding member, inside the photosensitive drum, so that the cost can be significantly reduced.

Further, a polymer layer having a high damping rate is formed between the cylindrical drum and the photoconductor layer so that the vibration transmitted to the polymer layer is attenuated in a hysteresis manner, so that the vibration is transmitted to the cylindrical drum. Vibration is cut off to prevent the occurrence of vibration due to the photosensitive drum, and high image quality and low noise of the apparatus can be reliably achieved.

Further, a polymer layer having a high damping rate is formed on the inner peripheral surface of the cylindrical drum so that the vibration transmitted to the polymer layer is attenuated in a hysteresis manner. High image quality and low noise of the device can be reliably achieved.

Further, since the internal loss of the hysteresis attenuation is increased by using rubber or the like having a weak bonding force at the molecular level as a material of the polymer layer, it is possible to attenuate the vibration generated on the photosensitive drum more quickly. As a result, higher image quality and lower noise of the apparatus can be achieved more reliably.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is an envelope characteristic diagram of friction attenuation in the above embodiment.

FIG. 3 is a characteristic diagram showing an internal loss of hysteresis attenuation.

FIG. 4 is a configuration diagram illustrating a configuration of a second embodiment.

FIG. 5 is a configuration diagram illustrating a configuration of a third embodiment.

FIG. 6 is a configuration diagram illustrating a configuration of a fourth embodiment.

FIG. 7 is an enlarged sectional view of a cylindrical drum according to a fifth embodiment.

FIG. 8 is an enlarged sectional view of a cylindrical drum according to a sixth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoconductor drum 11 Photoconductor layer 12 Cylindrical drum 13 Polymer layer 2 Charging unit 3 Exposure unit 4 Developing unit 5 Transfer unit 6 Peeling unit 7 Cleaning unit 71 Cleaning blade 8 Sliding member 9 Registration roller 10 Paper transport unit

Claims (8)

[Claims] 1. An image forming apparatus comprising: a cylindrical drum made of a conductor having a photoconductor coated on its surface; and a photosensitive drum comprising flanges attached to both ends of the cylindrical drum. An image forming apparatus comprising a sliding member that inscribes and adds rolling friction. 2. An image forming apparatus having a photosensitive drum comprising a cylindrical drum made of a conductor having a photoconductor coated on its surface and flanges attached to both ends of the cylindrical drum, the cleaning unit being interposed therebetween. An image forming apparatus, comprising a sliding member that externally contacts the photosensitive drum and adds rolling friction between the transfer unit and the charging unit. 3. An image forming apparatus having a photosensitive drum comprising a cylindrical drum made of a conductor having a surface coated with a photoconductor and flanges attached to both ends of the cylindrical drum. An image forming apparatus comprising a sliding member that moves along the inner peripheral surface and moves along the inner peripheral surface to add rolling friction. 4. The image forming apparatus according to claim 1, wherein the sliding member has a roller shape. 5. An image forming apparatus having a photosensitive drum comprising a cylindrical drum made of a conductor having a photoconductor coated on its surface and flanges attached to both ends of the cylindrical drum, wherein an inner periphery of the photosensitive drum is provided. An image forming apparatus comprising a granular sliding member that moves along a surface. 6. A photosensitive drum comprising a polymer layer having a high attenuation rate formed on the outer peripheral surface of a cylindrical drum made of a conductor and a photoconductor layer applied on the surface of the polymer layer. Image forming apparatus. 7. A photosensitive drum comprising a polymer layer having a high attenuation rate formed on the inner peripheral surface of a cylindrical drum made of a conductor and a photoconductor layer applied on the outer peripheral surface of the cylindrical drum. Characteristic image forming apparatus. 8. The image forming apparatus according to claim 6, wherein said polymer layer is formed of rubber.