JPH03231789A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To obtain an electrophotograph of high quality corresponding to a multiple number of applications with one type of electrophotographic device by providing a multiple number of photosensitive bodies provided with an image range periphery surface and a position restriction periphery surface for the main body. CONSTITUTION:A multiple number of photosensitive bodies which are exchangeable with the main body are provided, and these photosensitive bodies are provided with the image range periphery surface and the position restriction periphery surface positioned at the edge part of the periphery surface. Then, the relative diameter of the image range periphery surface and the position restriction periphery surface are each made different corresponding to the characteristics of a multiple number of photosensitive bodies. For example the space G1 between the photosensitive drum 1 and the developing sleeve 82 is kept constant by a restricting roll 85, and the restricting roll 85 is attached on the same shaft as the developing sleeve 82 and is abutted to an edge part of the photosensitive drum 1. Then the central part of the photosensitive drum is made the image range periphery surface, and its edge part is made the position restriction periphery surface 1'. Thus, the photosensitive body with the desired characteristic can be selected from the multiple number of photosensitive bodies and when the operation switch is turned ON, the desired electrophotograph can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic apparatus including a main body and a plurality of replaceable photoreceptors.

[Prior Art] Conventionally, photoreceptors used in electrophotographic devices generally include organic semiconductors such as zinc oxide, cadmium sulfide, and PVK, amorphous selenium-based photoreceptors, and amorphous silicon-based photoreceptors. Are known.

In conventional electrophotographic apparatuses, the above-mentioned photoreceptors are selected depending on various uses, so one electrophotographic apparatus uses only one photoreceptor. In recent years, the electrophotographic equipment field has diversified into personal, medium- to high-speed abrasive machines, color, and special purpose machines, and customers who want to better reproduce vermilion, firmly reproduce blue, and reproduce by erasing blue, etc. There are various demands.

For example, when making a large number of copies, it is necessary to keep the running cost low even if the initial cost is high, to reduce maintenance without hassle, and to obtain stable high-quality copies. In such cases, it is known to use a photoreceptor with a long life and stable charging characteristics, such as an amorphous silicon-based photoreceptor.
In addition, there are cases where a low initial cost is desired when a large number of copies are not made, and in such cases, it is recommended to use a photoreceptor that does not have a very long lifespan or is inexpensive, such as an OPC photoreceptor. It has been known.

[Problems to be Solved by the Invention] However, since conventional electrophotographic apparatuses use only one type of photoreceptor, different electrophotographic apparatuses are required for each use.

Therefore, it is an object of the present invention to provide an electrophotographic apparatus that can be used for a variety of purposes using a single apparatus main body.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a plurality of replaceable photoreceptors with respect to the main body, and these photoreceptors have a peripheral surface of an image area and a peripheral surface of the image area. In the electrophotographic apparatus, the relative diameter of the image area circumferential surface of the photoconductor and the position regulation circumferential surface is different depending on the characteristics of the plurality of photoconductors. It is configured as follows.

Since the present invention has the above configuration, a photoreceptor having desired characteristics is selected from among a plurality of photoreceptors, and the photoreceptor is mounted on the main body. Then, by turning on an operation switch or the like, a desired electrophotograph can be obtained. As described above, according to the present invention, one type of electrophotographic apparatus can be used for a plurality of purposes.

At this time, according to the present invention, since the photoreceptor is provided with a position regulating circumferential surface, the position suitable for the selected photoreceptor is automatically regulated. Since the interval is regulated to an optimum value, it is possible to obtain high quality electrophotographs.

[Example] Embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a schematic diagram of an overall embodiment in which the present invention is applied to an electrophotographic apparatus using a drum-type photoreceptor.

In the figure, reference numeral 1 denotes a photoconductor, and the first photoconductor is an organic photoconductor (OPC) type photoconductor IA, or the second photoconductor is an amorphous silicon (abbreviated as A-Si) photoconductor.
It represents the system photoreceptor IB.

The surface of the document 3 placed on the copying machine main body is illuminated by the document illumination light source 4, and the reflected light I shown by the chain line is reflected through the mirrors M, M, the lens 5, and the image exposure filter 6A or 6B. As exposure I or step 2, the light reaches the photoreceptor 1 and forms an image.

Since the photoreceptor 1 is uniformly charged in advance by the charger 7, an electrostatic latent image is formed on the photoreceptor 1 by the reflected light.

The charger 7 performs corona charging using a belt wire 71, and is provided with a grid wire 72 to stabilize the corona charging, and a grid bias is connected between the grid wire 72 and the ground via a resistor.

The charging current and grid voltage flowing through the charger 7 are controlled in correspondence with the photoreceptors IA and IB, respectively, as will be described later. This latent image is then developed by a developing device 8 and visualized as a toner image.

After the toner scattered from the developing device 8 is collected by the bias roller 37, the toner is charged with the same polarity as the toner by the post charger 28, thereby improving the transferability of the toner.

On the other hand, the transfer material 10 is fed out one by one by the paper feed roller 9, is sent out by the registration roller 11 in synchronization with the toner image on the photoreceptor 1, and the toner image on the photoreceptor drum 1 is transferred onto the transfer material by the transfer charger 12. Then, the transfer material is separated from the photoreceptor 1 by a separation charger 13, the toner image is fixed by a fixing device 14 consisting of a heating and pressure roller, and the toner image is discharged onto a paper discharge tray 19. Further, the toner image remaining on the photoreceptor 1 after transfer separation is removed by cleaning means 2.
The toner is removed by the pre-exposure P1 irradiated onto the photoreceptor 1 from the light source 4 through the slits S, S, and the pre-exposure filter 16, or the pre-exposure P2 irradiated by the pre-exposure lamp 17. After the surface potential on the photoreceptor i is removed, it is repeatedly used for copying.

Here, the photoreceptor IA was an e-charging OPC photoreceptor, which was fabricated on an aluminum cylinder with an outer diameter of 108 mm by the following method.

Casein ammonia water (
Coating material (11.2 g of casein, 1 g of 28% ammonia water, 222 ml of water) was applied by a coating method and dried to form a subbing layer with a coating weight of 1 and 0 g/m2.

Next, 1.0 parts by weight of a charge generating substance represented by formula (1) butyral resin (
S-LEC BM-2: 1 part by weight (manufactured by Tanemizu Kagaku ■) and 30 parts by weight of isopropyl alcohol were mixed using a ball mill dispersion machine.
Spread out time. This dispersion was applied onto the previously formed subbing layer by a dip coating method and dried to form a charge generation layer. The film thickness at this time was 0.3 microns.

Next, 1 part by weight of the charge transporting substance represented by formula (2), 1 part by weight of polycarbonate resin (Nipilon S-2000, manufactured by Mitsubishi Gas Chemical), and 6 parts by weight of dichloromethane were mixed and dissolved by stirring with a stirrer. This liquid was applied onto the charge generation layer by dip coating and dried to form a charge transport layer. The film thickness at this time was 16 microns.

The photoreceptor IB is eV conductive A-5i photoreceptor and has an outer diameter of 1
On a 08 mm aluminum cylinder, 3μ of the lower pronging layer C-5i:P:)l] and the photosensitive layer [A-5i
H:B] 25μ, upper blocking layer [A-5iC
:B:H 05μ, and surface protective layer [8-5iC:
H] was sequentially deposited to a thickness of 05 μm.

Figure 2 shows 0PCr:! L shows the relative sensitivity of the light body IA and A-3i the ill-sensitivity light IB, and FIG. 3 shows the spectral distribution of the light source 4 for illuminating the document.

The image exposure filters 6A and 6B are filters that cut wavelengths of 545 nm or more and 630 nm or more, respectively, and may be made of colored glass, a dichroic ivy filter, or a colored transparent plastic filter.

Figure 4 shows a stiff image exposure filter 6A.

It showed a transmittance of 6B. Image exposure filter 6A is OPC
Suitable for photoreceptor IA, image exposure filter 68 is A-5
Suitable for irritating photo IB.

When a halogen lamp is used as a light source for document illumination and there is no image exposure filter, the oPC photoreceptor IA produces relatively strong red light, which deteriorates the reproducibility of red ink, etc., so it is used as a red cut filter for image exposure. It uses a filter. The maximum sensitivity wavelength of OPC5 optical body IA is 55
0 nm, and if the long wavelength component is cut too much, for example, if it is cut at 600 nm, the efficiency of image exposure will deteriorate, and the lighting voltage of the halogen lamp must be increased, resulting in problems such as increased cost and temperature rise.

Due to the balance between the two, image exposure filter 6A halo 45
Cut more than nm.

Next, the maximum sensitivity wavelength of A-5i5 light body IB is 678r++
The applicant of the present invention proposed in Japanese Patent Application Laid-Open No. 60-24917 whether it is most efficient or best to use light in the vicinity of 678r++u.
As disclosed in No. 0, when the wavelength of image exposure is long, especially long wavelength light around the maximum sensitivity wavelength, I
Since the F electric potential decreases and the dark decay increases, the density of the copied image decreases and ghost images occur. Furthermore, the above-mentioned problem of red color reproducibility also arises.

For this reason, the image exposure filter 6B for A-5i bad exposure IB cuts over 630 mm.

Here, a ghost image is one part left over from the previous copying process.
This is a phenomenon that appears as an image in the next copying process.

Next, pre-exposure will be explained. When the OPC photoreceptor IA is used, the irradiation light from the halogen lamp 4, which is a light source for document illumination, is transmitted through the pre-exposure filter 16 as pre-exposure P1. As the pre-exposure filter 16, a red filter that cuts short wavelength light of 600 m or less is used.

This is to improve the life of the photoreceptor, since the OPC photoreceptor suffers from light damage when irradiated with short wavelength light.

A When using the 3i5 light body IB, the pre-exposure shutter 18 shuts off the above-mentioned pre-exposure Pl, and the pre-exposure lamp 17
A 610 m LED lamp is used as pre-exposure P2. The reason for this is as mentioned in the explanation of image exposure above.
band! This prevents the potential from decreasing.

Next, the applied voltage will be explained.

Table 1 shows the voltage applied by each voltage applying means, which was switched corresponding to the OPC photoreceptor IA and the A-5i photoreceptor IB.

Table 1 The OPC photoreceptor IA and the A-5i bad photoreceptor IB have different charging characteristics; at the same charging current, the OPC photoreceptor IA or the photoreceptor surface dark potential VD will be higher. Therefore, A-3i Nausea I
When using B, a larger band current Ip is required compared to when using the opct photon IA.

Here, the OPC photoreceptor IA has a dark potential ■. Despite the setting of -650V, the dark potential of A-3i
. The reason why I set it to -480V rather than -650V is that the dark potential V0 of A-3t nausea photo IB is set to -650V (-480V).
In order to increase the voltage to 50V, the charging current Ip must be made very large, and the capacity of the high voltage transformer 32 of the IF electric appliance 7 must be increased, which would make it very expensive, so the dark potential should be slightly increased. It is set low.

Grid voltage V. If the dark potential is set low, the dark potential at the same charging current decreases, so the charging current must be increased to obtain the same dark potential.

Since it is not desired to increase the charging current too much, in the present example, the grid voltage VG was set to a higher value in the case of the A-5i photon than in the case of the 0PC4 photon.

Next, the reason why the setting value of the DC component of the developing bias is different is that the OPC photoconductor IA and the A-Si photoconductor IB in this embodiment are different.
This is because the bright potential VL of
The difference is due to the difference in dark potential between the two photoreceptors, the difference in sensitivity characteristics, the difference in image exposure conditions, etc.

In the above copying process, when the type of photoreceptor to be used is selected using a photoreceptor column selection switch (not shown), the control circuit controls the image exposure, pre-exposure, charging, transfer, etc.
0PCF for separation, development, etc. conditions! 1. It is set to be switched to one that passes through the light body IA and the A-5i ill-sensation light IB, respectively.

Alternatively, instead of the photoconductor column selection switch, a photoconductor detection means for identifying the type of photoconductor is provided, and a control circuit automatically performs fishing based on the identification signal detected by the photoconductor detection means.
OPC photoconductors IA and A-
The setting may be changed to one suitable for 5i ill-sensitivity IB.

FIG. 5 is a cross-sectional view of the main parts of the developing device 8 used in the wooden top embodiment, in which 81 is a hopper containing a developer (-component toner, two-component toner, etc.), and 82 is a hopper that extends circumferentially in the longitudinal direction. A non-magnetic cylinder (hereinafter referred to as a sleeve) serving as a developer supporting member is rotatably attached between the side plates of the hopper with a part of its surface exposed to the outside through the opening of the hopper.

83 is a magnet roller provided concentrically and fixedly within the sleeve, and has a plurality of magnetic poles N1, N2, N3, Sl, and S2.
・S3 is formed parallel to the longitudinal direction of the circumferential surface. 86 is connected to the hopper 81 with a gap G2 between it and the sleeve 82.
1 is a photoreceptor as a latent image holding means which is rotatably supported on the copying machine body (not shown) in the direction of the arrow, and a gap G1 is provided between the plate and the plate as a developer layer thickness regulating means. The sleeves 82 are arranged in parallel.

Sleeve 82 or not shown! When the developer T receives a driving force from source A and rotates in the direction of the arrow, the developer T is restrained on the sleeve by supporting forces such as magnetic force and electrostatic force, and is conveyed in the direction of the arrow by the rotation of the sleeve, and is transported by the plate 86. It is applied to a constant layer thickness t. On the surface facing the photoreceptor 1, this coated developer T electrostatically jumps or stretches across the gap G1 in accordance with the latent image pattern on the photoreceptor, and is transferred to the latent image surface for development.

Here, the distance G1 between the photosensitive tram 1 and the developing sleeve 82
is kept constant by the regulating roller 85. As shown in FIG. 6, the regulating roller 85 is attached coaxially with the developing sleeve 82, and is in contact with the end of the photosensitive tram 1.

The center portion of the photosensitive drum serves as an image area circumferential surface, and the end portion thereof serves as a position regulating circumferential surface 1'.

Figure 6 (A) shows an example in which the ○PC photoconductor IA is installed.If the radius of the image area circumferential surface at the center of the photoconductor is the same as that of the position regulating circumferential surface at the end, the photoconductor The distance G1 between the body 1 and the developing sleeve is given by the difference between the radius R2I of the regulating roller 85 and the radius R2 of the developing sleeve.

That is, G1=R21R2.

FIG. 6 (8) shows an example in which the A-5i photoreceptor IB is installed. In this case, the distance G1 between the photoreceptor IB and the developing sleeve 82 is expressed by the following formula: Gl = R+++Rz+ (
R1+R2) In the formula, J is the radius R21 of the contact portion of the photoreceptor IB with the regulating roller 82, the radius R1 of the regulating roller 85, and the radius R2 of the opposing portion of the photoreceptor IB with the developing sleeve 82 is the radius of the developing sleeve. be.

The regulating rollers 85 are disposed at both ends of the developing sleeve 82 and rotated in contact with both ends of the photosensitive drum 1, thereby maintaining this distance G1.

Next, the results of examining the difference in the shape of the photoconductor when using the OPC photoconductor IA and the A-5i photoconductor IB, the distance G1 between the photoconductor and the sleeve that changed due to this, and the initial image evaluation are shown in Table-- Shown in 2.

As shown in Table 2, when using the OPCG photoconductor IA, the distance G1 between the photoreceptor and the sleeve is 300 μm, and A-
When the Si photoreceptor IB is used, the distance G1 between the photoreceptor and the sleeve is 260 μm.

As mentioned above, the dark potential o of the A-5i photosensitive IB is O
Since it is set lower than that of the PC photoreceptor IA, the density of the copied image will be lower if left as is. Therefore, the distance G1 between the photoreceptor and the developing sleeve is narrowed.

When copying was carried out under these conditions using the OPC photoreceptor IA and the A-5i photoreceptor IB, a high-density, clear, and high-quality image with good red reproducibility was obtained.

(Comparative Example 1) The shape of the A-3i photoreceptor IB was the same as that of the OPC photoreceptor IA, and G1 was 300 μm, and the other configurations were the same as in Example 1.

As shown in Table 2, the image density was low when A-3i bad sensitivity IB was used.

(Comparative Example 2) The shape or dimensions of photoreceptor IA and photoreceptor IB were the same as those of photoreceptor IB in Example 1, and the other conditions were the same as in Example 1.
It has the same configuration as . In this configuration, G1 is set to 260 μm to match the characteristics of the A-5i illuminant IB, and as shown in Table 2, when using the opci illuminant IA, the characters become thick and the image quality is Or it was defective.

By making the shapes of the OPC photoconductor IA and the A-3i5 photoconductor IB different in this way, it is possible to adjust the photoconductor and sleeve according to the characteristics of each photoconductor without changing the sleeve 82, regulating roller 85, etc. on the main body side. By optimizing the interval G1 between the OPC photoreceptor and the A
-5i and both can be suitably used.

In Example 1 shown in FIG. 6CB), A-3ii light body IB
Is this an example in which the outer diameter of the development position regulating surface 1' is reduced?
The relative position of the image area surface of the photoconductor and the development position regulating surface 1'' is important; for example, the radius R1+ of the development position regulation surface of the photoconductor IB is set to φ54. 0mm and the radius R1 of the image area surface of the photoconductor IB is 54.04, the distance G1 between the photoconductor IB and the sleeve 82 is G1 = all + R21 - (R1 + R2)
= 5 4 + 16.3- (54,04+ 1
5) = 0.26 mm = 250 μm, and as shown in Table 2, the same effect as in Example 1 can be obtained.

FIG. 7 is a schematic diagram of a main part of another embodiment in which the present invention is applied to an electrophotographic apparatus using a tram type photoreceptor.

The only difference from Example 1 is the shape of the photoreceptors IA and IB. That is, the radius R of the developing position regulating circumferential surface 1'' of the photoconductor IA is larger than the radius R1 of the image area surface, and the radius R of the developing position regulating circumferential surface 1'' of the photoconductor IB is equal to the radius R1 of the image area surface. They are the same. However, the radius R21 of the regulating roller 85 is 16.26 mm. Regarding the distance G1 between the photoreceptor and the developing sleeve, the distance G1 between the photoreceptor IA and the developing sleeve 82 is 54.04.
+11i, 26- (54,0+16.O)=0.
30mm = 300μ Distance G1 between photoreceptor IB and developing sleeve 54+16.26 - (54+1[i,0)=
0.26mm=260μ, and as shown in Table 2, the same effect as in Example 1 can be obtained.

FIG. 8 is a schematic diagram of a main part of another embodiment in which the present invention is applied to an electrophotographic apparatus using a drum type photoreceptor.

The configuration of the photoreceptor IA is slightly different from the second embodiment shown in FIG. 7(A). That is, in Example 2, photoreceptor I
The shape of the photoreceptor itself was changed in order to make the radius all of the development position regulating circumferential surface 1 of A larger than the radius R1 of the image area surface. The radius R1+ is made larger than the radius R1 by covering the tube 101 with
The outer circumferential surface of the developing position is the development position regulating surface.

Even with such a configuration, as shown in Table 2, Example 1.
It is clear that the same effect as 2 can be obtained.

FIG. 9 is a sectional view of essential parts of an embodiment of the cleaning device of the present invention.

The cleaning device 200, which is disposed close to the photoreceptor rotating in the direction of the arrow, includes a cleaning plate 201.
This is placed in pressure contact with the surface of the photoreceptor.
On the upstream side thereof, the surface magnetic roller 202 is maintained at a constant distance G3 by a cleaning position regulating roller 203.
are arranged rotatably in the direction of the arrow, that is, the photoreceptor 1
The counter is arranged so that it rotates in one direction,
It rotates at a circumferential speed that is 80% of the circumferential speed of the photoreceptor.

The distance G3 between the photoreceptor 1 and the magnetic roller 202 is the 10th
As shown in the figure, the cleaning position is kept constant by a cleaning position regulating roller 203. This regulating roller is magnetic roller 202
It is attached coaxially with the photoreceptor 1 and abuts on the end of the photoreceptor 1.

Furthermore, place the scraper 208 or magnetic roller surface on the appropriate place and
, it is profitable to reduce the interval of 1 mm.

With this structure, the toner removed from the photoreceptor forms a magnetic brush, thereby removing foreign matter from the surface of the photoreceptor.

Next, the regulation of the interval G3 will be described below.

As shown in FIGS. 9 and 10, the magnetic roller 202
The shaft 22a is attached to a holder 209 via a bearing 206, and the holder 209 is movably attached to the housing 205, and is moved in the direction of the photoreceptor 1 along a guide path of the housing 205 (not shown). Being pressed.

203 is directly attached to the shaft 202a or bearing 207
These are regulating rollers attached to both ends of the magnetic roller 202 via
2, the interval G3 is regulated.

If the distance G3 between the magnetic roller surface and the photoreceptor surface is large, the magnetic brush of the magnetic roller 202 strongly rubs the photoreceptor 1, damaging the photoreceptor 1 surface and degrading the image quality. In addition, if the gap G3 is small, that is, if the sliding force is small, it may not be possible to sufficiently remove substances such as rosin, talc, corona products, etc. that strongly adhere to the surface of the photoreceptor 1, or the developer may not be able to be removed from the photoreceptor. Since the developer is lightly pressed against the photoreceptor 1, some or all of the components of the developer may adhere to the surface of the photoreceptor 1 in the form of a film, resulting in a decrease in image quality. The appropriate value for the distance G3 is the magnetic roller 202, the material of the photoreceptor 1, and the 6B roller 2.
Although it varies depending on the relative speed of photoreceptor 1 and photoreceptor 1,
When using the opct light body IA, the interval G3 is 0.
The distance MD was preferably 8 mm, and when A-5i Nausea Photo IB was used, the distance MD was preferably 0.9 mm.

If you think about the reason, A-5i5 optical body IB is opc
Is it possible to clean the PC photoconductor IA with a weak force because it is harder and has weaker adhesion than the photoconductor IA? ○The PC photoconductor IA is soft and has foreign substances such as rosin and talc embedded in it, so it should be cleaned with a strong force. This seems to be because there is a need to rub it.

If the sliding force of the cleaning roller is too strong, the photoconductor will be damaged and the image quality will deteriorate. Therefore, it is preferable that the sliding force be as weak as possible within the range that allows sufficient cleaning, depending on the type of photoconductor as mentioned above. It seems that the appropriate value is off.

FIG. 11 is a schematic diagram of main parts showing the arrangement relationship between the photoreceptors IA and IB, the developing sleeve and the magnetic roller.

Here, the distance G3 between the photoconductor IA and photoconductor IB and the magnetic roller is given by the following formula: G3=R12+R32 (R1+R3) In the formula, R1 is the radius of the photoconductor facing the magnetic roller RI2 is the cleaning position of the photoconductor The radius R3 of the contact portion with the regulating roller and the radius R32 of the magnetic roller are the cleaning position regulating roller radius.

Differences in the shape of the photoconductor when applying the OPC photoconductor IA and A-5r photoconductor IB, the distance G1 between the photoconductor and the sleeve that changed accordingly, the distance G3 between the photoconductor and the 6ft roller, and the initial and Table 3 shows the results of examining the images after durability.

The durability was evaluated by making 50,000 copies of the OPC photoreceptor IA and 800,000 copies of the 'j Healer A-S i photoreceptor.

When 50,000 copies were made using the OPC photoreceptor IA with this configuration, clear and high-quality images with good red reproducibility were obtained.When 800,000 copies were made using the A-3i photoreceptor, , red color reproducibility was good, image density was stable, and clear, high-quality images were stably obtained.

(Comparative Example 3 with respect to Example 4) The shapes of photoreceptor IA and photoreceptor IB were the same as that of photoreceptor IA of Example 4.
The other parts are the same as those of the fourth embodiment.

This configuration is set according to the characteristics of the OPC photoreceptor IA, and as shown in Table 3, when A-5t bad sensitivity 1 is used, the image density is low at the initial stage, and after durability it reaches 600,000 yen. The image quality deteriorated when copying several sheets.

(Comparative Example 4 with respect to Example 4) The shapes of photoreceptor IA and photoreceptor IB were changed to those of photoreceptor IB of Example 4.
The other parts are the same as those of the fourth embodiment.

This configuration is set according to the characteristics of the A-5i photoreceptor IB, and as shown in Table 3, when using the OPC photoreceptor IA, the image quality will initially be poor due to the large letters. Inferior durability: 32.5°C 85% after 20,000 copies
Image blur occurred in RH environment.

In this way, OPC photoconductor IA and A-5i 5-photoconductor IB
A single electrophotographic apparatus can be created by optimizing the distance G1 between the photoreceptor and the developing means and/or the distance G3 between the photoreceptor and the cleaning means in accordance with the characteristics of each photoreceptor with a simple configuration of different shapes. In this case, it is possible to suitably use both the OPC photoreceptor and the A-5i photoreceptor.

FIG. 12 is a schematic diagram of main parts of another embodiment (Embodiment 5) in which the present invention is applied to an electrophotographic apparatus using a drum-type photoreceptor.

Embodiment 4 shown in FIG. 11 differs only in the shapes and configurations of photoreceptors IA and IB.

That is, in Example 4, corresponding to the characteristics of each photoreceptor,
The shape of the photoreceptor itself was changed as a method of appropriately setting the distance G1 and the distance G2, but in this embodiment, this is done by appropriately wrapping the tube 101 around the developing position regulating part and the cleaning position regulating part. .

As shown in Table 2, even with such a simple configuration, the same effects as in Example 4 can be obtained.

FIG. 13 is a cross-sectional view of the main part of another embodiment (Embodiment 6) of the cleaning device of the present invention.

The cleaning device 2 is installed approximately parallel to the axis of the photoreceptor 1 (
It has a casing 25 extending in a direction perpendicular to the plane of the paper,
A cleaning plate 21 made of an elastic material such as urethane rubber is attached to this in an appropriate manner, and one edge of the cleaning plate 21 is in pressure contact with the surface of the photoreceptor.

Inside the casing 25, a cleaning roller 22 made of a non-magnetic elastic material is attached rotatably in the direction of the arrow on the upstream side when viewed in the traveling direction of the photoconductor, and is installed to maintain a predetermined nip width via regulating rollers 23. A part of the surface is in pressure contact with the surface of the photoreceptor. As the cleaning roller, sponge-like silicone rubber, urethane rubber, etc. can be suitably used.

Further, as shown in the figure, a scraper 24 is disposed in the housing opposite the cleaning roller 22, and the distance lid between the scraper and the surface of the cleaning roller is maintained at 50 μm or less. In the past, foreign matter such as paper dust adhering to the surface of the cleaning roller was reliably removed by the scraper 24, and a thin layer of toner was formed without any paper dust on the downstream side of the scraper position in the running direction of the roller 22. Since the surface of the cleaning roller rubs against the image carrier in this state, the surface of the photoreceptor is prevented from being damaged by the cleaning roller due to the effect of "smoothing the toner".

Regulation of the contact pressure between the cleaning roller and the surface of the photoreceptor will be described below.

As shown in FIGS. 13 and 14, the shaft 22a of the cleaning roller 22 is attached to a holder 29 via a hair ring 26, and the holder 29 is movably attached to the casing 25 and is fixed. It is pressed toward the photoreceptor 1 along the guide groove of the illustrated housing 25 .

Regulating rollers 23 are attached to both ends of the cleaning roller 22 either directly on the shaft 22a or via hair rings 27, and contact the photoreceptor 1 to restrict the amount δ of the cleaning roller 22 entering the photoreceptor 1. By regulating the approach amount δ, it is possible to regulate the contact pressure and the nip width k. Here, it is important to regulate the contact pressure and the nip width.When the contact pressure is large, that is, when the nip width λ is large, the cleaning roller 22 strongly rubs the photoreceptor 1, so that the surface of the photoreceptor 1 is will be damaged and the image quality will be reduced. In addition, if the contact pressure is small, that is, if the nip width a is small, it may not be possible to sufficiently remove substances that strongly adhere to the surface of the photoreceptor 1, such as rosin, talc, or corona products, or the developer may not be able to be removed sufficiently. Since it is lightly pressed against the photoreceptor 1, some or all of the components of the developer may adhere to the surface of the photoreceptor 1 in the form of a film, resulting in a decrease in image quality. Does the appropriate value of the nip width vary depending on the materials of the cleaning roller 22 and the photoconductor 1, the relative speed of the cleaning roller 22 and the photoconductor 1, or is it better when the OPC photoconductor IA is used as the photoconductor 1?A-3i A larger width was required than when using the negative light IB.

FIG. 15 shows the photoreceptors IA and IB and the developing sleeve 82.
, is a schematic diagram of main parts showing the arrangement relationship of the cleaning roller 22. FIG.

Here, the amount of approach δ of the cleaning roller into the photoreceptor IA and photoreceptor IB is expressed by the following formula.

δ = R1 + R3 (R1° + R82) where R1 is the radius of the contact area of the photoconductor with the cleaning roller R12 is the radius of the contact area of the photoconductor with the cleaning position regulating roller R3 is the radius of the cleaning roller R3 □ is the radius of the cleaning roller This is the radius of the position regulating roller.

As shown in Table 3, when 50,000 copies were made using the 0PC5 optical element IA with this configuration, clear and high-quality images with good red reproducibility were obtained, and the A-5i image quality was improved. When 800,000 copies were made using this method, clear, high-quality images with good red reproducibility and stable image density were consistently obtained.

(Comparative Example 5 with respect to Example 5.6) The shapes of photoreceptor IA and photoreceptor IB were the same as that of photoreceptor IA of Example 6.
The other parts are the same as those of the sixth embodiment.

This configuration is set according to the characteristics of the OPC photoreceptor IA, and as shown in Table 3, when A-3i5 photoreceptor 1 is used, the image density is low at the initial stage, but after durability it will reach 500,000 yen. The image quality deteriorated when copying several sheets.

(Comparative Example 6 with respect to Example 5.6) The shapes of photoreceptor IA and photoreceptor IB were changed to those of photoreceptor IB of Example 6.
The other parts are the same as those of the sixth embodiment.

This configuration is set according to the characteristics of the A-3i photoreceptor IB, and as shown in Table 3, when using the ○PC photoreceptor IA, the image quality is poor in the initial stage due to thick characters. , Durability: 32.5℃85% after 30,000 copies
Image blur occurred in RH environment.

In this way, with a simple configuration in which the shapes of the OPC photoconductor IA and the A-5t photoconductor IB are made different, the distance G1 between the photoconductor and the developing means and/or the distance G1 between the photoconductor and the cleaning means can be adjusted according to the characteristics of each photoconductor. By optimizing the position of the OPC photoreceptor and the A-
51 photoreceptor can be suitably used.

In the above embodiment, a magnetic brush roller and an elastic roller are used as an example in which the shapes of each photoreceptor are made different so that the positions of the photoreceptor and the cleaning means are appropriate according to the characteristics of each photoreceptor. Of course, it can be applied to other cleaning roller systems as shown in Figure 2, but it can also be applied to blade-type cleaning, etc. By changing the shape of the photoreceptor, the contact pressure of the cleaning plate, the cleaning plate The contact angle, etc. may be changed.

In the case of a combination type of cleaning blade and cleaning roller, for example, as shown in the above embodiment, the cleaning plate and cleaning roller are configured to operate independently, and the cleaning roller is controlled by a position regulating roller. The positioning of the cleaning roller is optimized according to the photoconductor based on the relationship between the diameter of the image area circumference and the diameter of the position regulating circumference. In response to
By optimizing the position setting of the cleaning blade, the positions of the cleaning plate and the cleaning roller can be set appropriately for each photoreceptor.

In general, the appropriate values for development conditions, cleaning conditions, etc. vary depending on the type of photoreceptor, but by varying the shape of each photoreceptor, it is possible to optimize the development and cleaning conditions for each photoreceptor. I can do it.

In this way, with one electrophotographic copying device, 0PCfft,
Since the light body and A-5i5 light body can be used,
A photoreceptor can be appropriately selected depending on a plurality of uses.

That is, if you do not want to make many copies and want a low initial cost, you can select an OPC photoreceptor that does not have a very long life but is inexpensive.

Note that if the number of copies is small, the interval between photoconductor replacements due to lifespan will be longer, so even if an OPC photoconductor is selected, the photoconductor replacement frequency will be low, and in this respect, it is not easy to forget. It's something you don't feel. Also, the amount of copies is large,
If you want to be able to consistently obtain high-quality copies even if the initial cost is high, and to reduce the hassle of replacing the photoconductor (reduced maintenance), it is recommended to It is possible to select the A-5i sensitizer, which has stable characteristics.

In the above embodiments, two types of photoreceptors were used as the photoreceptors, but photoreceptors of 3 fm or higher may also be used.

Further, although an example of a -f conductive photoconductor is shown, a +-ii conductive photoconductor may also be used.

Further, it is also possible to use a photoreceptor having +f'H property and monocharging property. However, in this case, it is necessary to take measures such as using reversal development on one side or replacing the developing device and also changing the polarity of the IF charge, transfer, minute charge, etc. In addition, as the photoreceptor, PC and A-5i are shown as examples, but zinc oxide, cadmium sulfide, amorphous selenium, etc. may be used in appropriate combinations.

[Effects of the Invention] As explained above, the photoconductor has an image area circumferential surface and a position regulating circumferential surface, and a plurality of photoconductors having these circumferential surfaces are prepared for the main body. By simply selecting a desired photoreceptor and mounting it on the main body, various positions suitable for the characteristics of the selected photoreceptor are automatically regulated or set. Therefore, according to the present invention, high quality electrophotographs can be obtained for a plurality of uses using one type of electrophotographic apparatus.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an overall example in which the present invention is applied to a drum-type photoreceptor, and FIG. 2 is a schematic diagram showing an example of an organic photosemiconductor-based photoreceptor and an amorphous silicon-based photoreceptor used in this example. A spectral sensitivity characteristic diagram, FIG. 3 is a spectral distribution characteristic diagram of the Heroken lamp similarly used in this example, FIG. 4 is a light transmission spectral distribution characteristic diagram of the image exposure filter, and FIG. 5 is a developing device section. FIG. 6 is a front view of the first embodiment showing the relationship between the photoreceptor and the developing sleeve, in which (A) shows the photoreceptor IA, and (B) shows the photoreceptor IA. Body I
FIG. 7 is a front view of the second embodiment showing the relationship between the photoreceptor and the developing sleeve similar to that in FIG. , FIG. 8 is a front view showing a third embodiment different from FIGS. 6 and 7, and its (A+, (B
) are front views showing examples of the photoreceptor, FIG. 9 is a side sectional view showing an example of the cleaning device, FIG. 10 is a front view thereof, and FIGS. 11 and 12 are the photoreceptor and the developing sleeve. , a front view of the fourth and fifth embodiments showing the arrangement relationship of the magnetic rollers, etc.;
B) is a front view showing each example of the photoreceptor IB;
3 is a side sectional view showing another embodiment (Embodiment 6) of the cleaning device, FIG. 14 is a front view thereof, and FIG. 15 is a sixth embodiment showing the arrangement relationship of the photoreceptor, cleaning roller, developing sleeve, etc. In the front view of the example, (A) is of the photoreceptor IA,
And (B) is a front view showing each example of the photoreceptor IB. 1.1A, IB...photoreceptor, 1'...position regulating circumferential surface, 2, 200...cleaning device, 82...
・Developing sleeve, 85...Regulation roller. Other 4 people Fig. Wavelength (nm) Fig. Wavelength [nm] Fig. Fig. 6 (A) Fig. (B) Fig. 7 (A) (B) Fig. 8 (A) Fig. (B) Fig. Figure 0 Figure 1 Figure 12 Figure 3 Figure 4

Claims (1)

[Claims] 1. A main body is provided with a plurality of replaceable photoconductors, and these photoconductors have an image area circumferential surface and a position regulating circumferential surface located at an end of the circumferential surface. An electrophotographic apparatus, wherein the relative diameters of the image area circumferential surface and the position regulating circumferential surface of the photoconductor are different depending on the characteristics of the plurality of photoconductors. 2. The electrophotographic apparatus according to claim 1, wherein the relative diameters are different because the outer diameters of the position regulating peripheral surfaces are different depending on the characteristics of the plurality of photoreceptors. 3. An electrophotographic apparatus, wherein the position regulating circumferential surface according to claim 1 or 2 regulates the distance between the photoreceptor and the developing device or the cleaning device.