JPS5833262A - Image carrying body - Google Patents

Abstract

PURPOSE:To obtain an electrostatic recording device which is compact and also small in power consumption, by using a material constitution whose eddy-current loss is small, for at least a part of a base body of an image carrying body. CONSTITUTION:An inductive eddy-current loss containing three all of thickness for cutting magnetic permeability of a base body (image carrying body), electric resistance and an alternating field of the base body becomes a reference of selection in order to eliminate torque and Joule heat generated in the base body. As for a base body 211, in respect of a material quality, that which has small magnetic permeability and/or large electric resistance, generally speaking, a non-magnetic and non-metallic substance, for instance, synthetic resin, rubber, or ceramics, etc. are selected. It is also possible to constitute the whole body of synthetic resin, ceramics and hardened rubber. Also, as a result of taking notice that thickness (t) is concerned in said current loss as aquare-law, the base body part can be constituted, for instance, of a metallic sheet whose thickness is about 0.01mm.-2mm., a layer separated multi-concentric circle of the metallic sheet and said non-magnetic and non-metallic substance, or incorporating a piano wire in said non-magnetic and non-metallic substance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention forms an electrostatic latent image in an electrostatic recording device, and forms a toner image on the electrostatic latent image by receiving a supply of magnetic toner or toner mixed with a carrier. , relates to an image carrier, and more particularly relates to an integral structure of the image carrier.

#1! In an electrostatic copying machine that forms an electrostatic latent image using electrostatic charges, which is 111 of an electrostatic recording device in FIG. Indicates the commonly used type M of the developer carrier (hereinafter referred to as a developing roll) and explains the conventional problems. In Fig. 1, 10 is the image carrier, 11 is the image carrier 10. The drum or drum is an image-bearing layer that forms and carries the electrostatic latent image and toner image. A dielectric material is selected and used. Here, as an example, an example in which a photoconductive substance (hereinafter referred to as a photosensitive layer) is used as an image bearing layer will be described.

The drum 11 is further divided into several parts.

111 is a photosensitive layer 12f: a cylindrical base body to be directly held, 1
4 is a rotating shaft of the drum 11, 113 is a fitting member for the rotating shaft 114, and 112 is an arm for fixing the fitting member 113 and the base body 111F. Each of the members constituting the drum 11 has a shaft 14.
Otherwise, aluminum is generally used in consideration of mechanical strength and weight.

13 is a developing roll that supplies toner (hereinafter referred to as both magnetic toner and non-magnetic toner) to the surface of the photosensitive layer 12 of the T-image carrier 10; 131 is a sleeve that serves as a toner supporting surface; , fixed or clockwise or counterclockwise rotation.

132 has a plurality of magnetic poles in FIG. 1, and as it rotates, the magnetic field created by the magnetic poles moves, and the sleeve 131
FIG. 1 is an example of a magnetic roll that transports toner toward the photosensitive layer 12 at the top, and an example of a developing roll that transports toner by a moving magnetic field.

The rotation direction and speed of the magnet roll 1320 are determined by the strength of the magnetic field created by the magnetic poles, the number of magnetic poles, whether or not the sleeve 1310 rotates, the direction of rotation, the rotation speed, and the rotation speed of the image carrier 10.
In addition to the developing roll, which moves the magnetic field shown in Figure 1 and transports the toner, the sleeve rotates,
A type of developer roll (not shown) in which a magnet is fixed for development and other purposes also has all the problems of the salmon solved by the present invention.

Reference numeral 133 denotes the rotating shaft of the magnet roll 1320, which may sometimes include the rotating shaft of the sleeve 131. The toner is a magnetic toner that contains a magnetic material itself as described above, or a small needle-shaped magnetic material such as iron. Two-component toners using powder or the like as a carrier are also used.

Image carrier 10 and developing roll 1 commonly used in the past
The configuration of No. 3 is as described above, and the distance between the image carrier 10 and the developing roll 13 is a factor that greatly affects the developing performance. They are placed in close proximity so that they are electrically attracted by the charge on the image.

When the secondary image carrier 10 and the magnet reel 132 start rotating based on the design specifications, lines of magnetic force extending from the magnet reel 132 cause the drum 11 of the image carrier 10 to rotate. In particular, aluminum is cut as an example of forming the base body 111 near the developing roll 13. If we consider a stationary section, for example, an elongated section in the axial direction of the base body 111, the direction of the magnetic force that cuts the section becomes an alternating magnetic field that alternates between positive and negative.

Therefore, an induced eddy current is generated in the segment 6, which is a conductor, and the segment 6 is subjected to a force in one fixed direction. The section 8 is constrained to rotate freely on the rotating shaft 14, and the same force as the section 8 is applied to it.

Therefore, in FIG. 1, when the magnet roll 132 rotates clockwise, the base 111 (image carrier 10) made of a conductor receives a counterclockwise torque, and the base 111t
-11 In order to rotate clockwise in synchronization with document scanning for copying, a large amount of driving torque is required as a result of further adding compensation torque to offset the silk. Furthermore, adding a compensation torque (5-) also requires addition of compensation torque to the magnet roll 132 in order to provide a braking effect on the rotation of the magnet roll 132. Therefore, to drive the base body 111 (image carrier 10) and the magnet roll 132, a motor with a large output corresponding to the compensation torque is required.

Also, contrary to the above case, in FIG. 1, the magnet roll 1
32 rotates counterclockwise, a torque is generated in the base 111 made of a conductor in the direction of the hour hand. Therefore, when the base body 111 rotates clockwise, the driving rotational force of the base body 111 can be saved.

However, the rotational speed of the base 111, that is, the rotation speed of the image carrier 100
Rotational speed is specified by process speed,
For example, it is 1001 PM at most. On the other hand, magnet roll 132
The zero rotational speed is similarly specified and is much faster than the rotational speed of the image carrier IO, for example 500 RPM or more than 1500 RAM. Therefore, it cannot be said that this is necessarily beneficial for the rotation of the base body 1110.

In addition, in the conventional image carrier 10 in which aluminum or the like is used as the material for the substrate 111, in addition to the disadvantages due to the generation of torque described above, induced eddy currents are generated and the substrate 111 is heated.
By flowing through the base body 111, Joule heat is generated and the temperature of the base body 111 increases. Therefore, the heat is transferred to the photosensitive layer 12 which is in close contact with the substrate 111. For example, in the case of selenium or the like, there is a great possibility that the high temperature will cause deterioration of characteristics and deterioration of image quality. Of course, even if the developing roll is of the fixed magnet type, and is not the same as the above-mentioned rotating magnet roll type developing roll, when the image carrier rotates along the copying process, the line of magnetic force is cut off from the fixed magnet. As it moves, eddy currents will occur. However, in the case of fixed magnets, the generation of Joule heat becomes a problem when a high-speed copying type image carrier rotates at high speed.

As is clear from the above, an object of the present invention is to make the developing device compact by eliminating disadvantages caused by torque generated between the developing device and the image carrier, regardless of whether the magnet is rotating or fixed. An object of the present invention is to provide an image carrier that enables an electrostatic recording device with low power consumption.
Furthermore, the electrostatic record #1 test snow eliminates the temperature rise due to Zeel heat caused by eddy currents generated in the image carrier, extends the life of the photosensitive layer of the image carrier, and prevents interstitial deterioration due to heat. An object of the present invention is to provide an image carrier that enables the following.

The object of the present invention as described above is to provide an image bearing member to which toner is supplied each time by a developing device having a magnet of an electrostatic recording device, at least a portion of the base P1 of the image bearing member having a material composition with low eddy current loss. By using this, it is possible to couple with an image carrier characterized by the structure.

Preferred embodiments will be described in detail below.

The torque generated in the base is due to the induced current generated when the conductor, that is, the base cuts the alternating magnetic field, and the electromotive force I is proportional to the multiplicative product of the magnetic permeability and the conductor shape factor, such as [μt”/l] Here, 1 is the induced electromotive force, μ is the magnetic permeability of the conductor, t is the diameter (thickness) of the conductor, and 1 is the length of the conductor.

In addition, the Joule heat generated in the conductor causes induced eddy current loss W@
So, W is 11@cyCμ! It is said that it is proportional to the square of the thickness t of the conductor and the square of the magnetic permeability - as t3/ρ, and is inversely proportional to the electrical resistance ρ.

Note that the other factors for IC and We of the above two types are specified by the design of the electrostatic recording device, so they are omitted, and only the factors related to the substrate are taken out.

The above-mentioned objects of the invention are met by eliminating the torque and Joule heat generated in the substrate. In other words, E and W in the above two equations may be reduced or suppressed to the extent that they can be ignored. Therefore, the object of the present invention can be achieved by configuring at least the base body with the magnetic permeability p, the electrical resistance ρ, and the cutting thickness tttn of the base body under an alternating magnetic field. That is, the selection criterion can be the inductor current loss W, which includes all three factors μ, β, and t.

As is already clear, the substrate of the present invention is made of a material with low magnetic permeability and/or high electrical resistance, generally speaking, a nonmagnetic nonmetallic material such as synthetic resin, rubber, or ceramic. To be elected.

The base of the present invention may be entirely composed of the above-mentioned synthetic resin, ceramic 9-xJ-11 1h↓4, tsuku, and valued rubber, or if the magnetic field has a substantial effect, the TWA surrounding , for example, the first thickness t
As a result of paying attention to the fact that is related to 1 and W as the square of
It is possible to use only about 11 metal thin plates, a solar calendar multi-concentric configuration of a metal thin plate and the non-magnetic non-metallic material, or a configuration in which piano wire is woven into the non-magnetic non-metallic material.

Regarding the synthetic resin used for the substrate of the present invention, the electric resistance ρ
is much higher than that of metal, and the magnetic permeability μ is much lower, so there is no need to consider it except in special cases. It may be selected by paying attention to moldability, dimensional stability, mechanical strength, etc. For example, polyethylene terephthalate, vinylidene chloride, fluororesin, acrylic resin, nylon resin, polycarbonate F11 acetal, polysulfone, polyimide, thermoplastic polyester, phenolic resin, resin 7 resin, etc. is used. The upturned synthetic tree N may be used alone or as a composite material, and may also be mixed with glass fiber, carbon fiber, etc.

The base 111 of the drum 11 is also coated with synthetic resin as the non-magnetic non-metallic material, rubbers such as styrene rubber, butadiene rubber, urethane rubber, silicone rubber, fluorine rubber, ethylene propylene rubber, chlorosulfonated polyethylene rubber, etc. Alternatively, Alfine rubber or the like, or even conductive rubber, can be used as the base by forming a shadow on a strong cylindrical member.

Next, examples will be shown and explained. Figure 2 shows a drum, except for the rotating shaft, which is constructed using the above-mentioned synthetic resin as the base. It is a fitting member for mounting the rotating shaft If, and 214 is a reinforcing plate having an opening to maintain the structural strength of the drum 21. Each member of the drum B described above was made of composite rIL resin. The rotation axis of the image carrier I is a metal shaft fitted with a fitting member 213. n is a photoconductive layer (photosensitive layer 11) made of selenium; 221 is a grounding cylindrical plate (layer) made of an electrical conductor that is in close contact with the photosensitive layer B; 215 to connect to the rotating shaft made of metal, and can be formed by pasting or attaching.

The figure shows a developing device that has a common type. The problem is the developer roll % 231 is the sleeve and 232 is the magnet roll. The rotational speed and direction of the image carrier and the magnetic marl 231 can be freely specified depending on the design.

The drum 21, especially the base 211, configured as described above does not generate silk due to magnetic induction and is lightweight, so the drive motor for the image carrier and the developing roll can be downsized and power can be saved. Furthermore, since the temperature of the photosensitive layer does not rise due to Joule heat, it is particularly useful for photoconductive materials that are prone to thermal deterioration, such as selenium. In addition, it is easy to assemble in one piece, has low material costs, and has many advantages such as a reduction in manufacturing costs due to its light weight.

As described above, the toner used for development may be either an N-component toner or a two-component toner.

Further, FIG. 3 shows an aluminum drum having a base body covered with a relatively thin aluminum cylinder and a synthetic rubber cylinder concentrically formed with a thickness that can isolate the aluminum cylinder from the influence of the magnetic field of a magnet roll. An example was given. Further, in this embodiment, a rubber magnet endless belt having several magnetic poles was used as a toner transport mechanism using magnetic field movement. 3111 is an aluminum base, and 3112 is the amount of synthetic rubber that coats the base 3111, and together they constitute the base 311. The wing is dielectrically charged on it by a multi-stylus etc.
(b) An integral layer, 321 is a grounding cylindrical plate. Earth cylindrical plate 32
1 is connected to the base 3111. Further, 331 is a sleeve, and 332 is an endless belt of rubber magnets stretched over small rolls 333, 334, and 335.

Further, FIG. 4 shows an image carrier having a base body 411 having a solar calendar multiple concentric cylinder structure made by alternately stacking aluminum thin sheets and synthetic resin plates. 4111 is an aluminum cylinder, 41
1 J is a synthetic resin cylinder. The developing roll l shows an example in which the sleeve 431 rotates and the magnet 432 is fixed.

In addition, in FIG.
2, 513 & 0 magnet roll 532, which is shown in the case consisting of an endless heddle-like photoreceptor stretched over the roll, is installed opposite to the developing roll &! Roll 511 is 1
It is made by integrally molding synthetic resin. Other rolls are unrelated to the present invention, but similar to the proximal roll 511, except for rolls that require special strength, synthetic rolls
By integrally molding the jI, it can also contribute to cost reduction and weight reduction.

Torque and cylinder heat generation can be reduced or eliminated14-, making it possible to achieve an electrostatic recording device with stable image quality.

[Brief explanation of the drawing]

1st Wi is a main part diagram showing the image bearing member and developing roll of the electrostatic copying machine, and Figures 112 and after are detailed explanatory diagrams of the present invention. This is an example of a bunjujizuke made of a concentric cylinder with multiple solar calendars made of thin aluminum plates and thin synthetic resin plates. Further, FIG. 5 shows - when the image carrier is an endless Pel F. 10, 20, 30 and Xun... Image carrier, 1
1, 21.31, 41 and 51...
Drums, 111, 211, 311 and 411...
...Base, 13.23,33. and group...
・Development reel. Agent Yoshi Kuwahara Collection 15- Conclusion 1 Figure A 20 Kui ζ Cow 11 48

Claims (4)

[Claims] (1) In an image carrier that receives toner from a developing device having a magnet of an electrostatic recording device, at least a part of the base of the image carrier is constructed using a material composition with low eddy current loss. An image carrier characterized by: (2) The image carrier according to claim 1, wherein a portion of the base of the image carrier where the magnetic field from the magnet of the developing device reaches the base is thin. (3) The image carrier according to claim 1 or 2, wherein the base of the image carrier is made of a non-magnetic material. (4) The image carrier according to any one of claims 1 to 3, wherein the base of the image carrier is made of synthetic resin.