JPS62267770A - Electrophotographic recorder - Google Patents

Abstract

PURPOSE:To improve the qualities of records formed on a recording medium, by providing a toner transferring section closer to the 1st magnet member side than the midpoint between the 1st and 2nd magnet members which carry magnetic toner along the surface of a toner carrying body. CONSTITUTION:Magnet members 1 and 2 are provided in a state where they are faced to each other with a prescribed gap (d) between them and the gap (d) is set in such a way that rays of light can enter into the gap and no magnetic interaction takes place between the members 1 and 2. The members 1 and 2 are respectively provided with numerous N- and S-magnetic poles which are alternately formed in their peripheral directions and carried into sleeves 11 and 12 freely rotatively. The sleeves 11 and 12 are coupled with each other by means of a toner carrier 3. The carrier 3 is provided with a photosensitive body 5 and a toner transferring section 8 is formed by positioning the photosensitive body 5 in the vicinity of the member 1 which is deviated toward the member 1 in the direction opposite to the toner carrying direction from the midpoint between the members 1 and 2. A light beam 10 modulated in accordance with picture/character information advances into the gap (d) by means of an optical scanning means 9 and optically scanned from the transparent supporting body 5a side of the photosensitive body 5. Therefore, the qualities of records can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic recording device used in copying machines, facsimile machines, optical printers, and the like.

[Prior Art] The present applicant has previously proposed a new electrophotographic recording method that reduces the number of steps in Japanese Patent Application No. 60-99369, in which a transparent support, a transparent electrode, and a photoconductive layer are Using a photoreceptor with a 3B structure, a charged toner is transported onto the surface of a photoconductive layer, and light is scanned from the transparent support side at a toner transfer section, and the toner is positioned on the surface of the photoconductive layer scanned by this light. A charge having a polarity opposite to that of the toner that has not been optically scanned is injected into the toner, and the toner charged to the opposite polarity is transferred to a recording medium via a transfer means.

Furthermore, in Japanese Patent Application No. 61-380, in order to convey toner along the surface of a photoconductive layer, a pair of magnet members each having a large number of magnetic poles are arranged on the side of a transparent support with a gap through which light can enter. The toner is transported by rotating both magnet members in the same direction, and light scanning is performed from the transparent support side to a toner transfer section provided at an equal distance from both magnet members, thereby transferring the toner to the recording medium. The configuration shown is as follows.

[Problems to be Solved by the Invention] As described above, in the device in which toner is transported by a pair of magnetic members, the toner on the sleeve covering the magnetic member or on the toner transport body is moved along the magnetic field created by each magnetic pole of the magnet member. The magnetic toner forms spike-shaped toner chains, and these toner chains are transported while rotating in a direction opposite to the direction of movement of the magnet member due to the movement of the magnetic field due to the rotation of the magnet member. Due to the balance of magnetic force, there is a region where toner transportation is hindered. That is, as shown in FIG. 4, when a pair of magnet members 1.2 is used, the magnetic field of the magnet member 1 is dominant in a region A near one of the magnet members 1 on the toner conveying body 3. In the region C near the other magnet member 2, the magnetic field of the magnet member 2 is dominant, and the toner 4 is smoothly transported by the movement of the magnetic field as the magnet members 1 and 2 rotate. In the intermediate region B of the member 1.2, a composite magnetic field is formed by both the magnet members 1.2, making it difficult for the toner 4 to be smoothly conveyed.

Especially when the distance from both magnet members is long on the center line P located at the midpoint of both magnet members 1.2, the magnetic force exerted by both magnet members is weak, and the magnetic force generated by both magnet members is the same. Since a composite magnetic field as shown in the vector diagram is formed, the magnetic force in the toner transport direction becomes almost zero on the center line P, and there is only the magnetic force in the direction F perpendicular to the toner transport direction. Therefore, the toner 4 is not conveyed smoothly in this intermediate area, and unevenness occurs in the toner 4 located in the intermediate area. However, if the gap d is made too small, the two magnet members become a kind of magnetic gear due to magnetic interaction, and when one magnet member is rotated in one direction, the other magnet member is rotated in the opposite direction. This force acts, making it difficult to rotate both magnet members in the same direction, which impedes toner conveyance. Therefore, as shown in the above-mentioned conventional example, a toner transfer section is provided on the center line P,
In a configuration in which the toner 4 is transferred by optical scanning to the photoreceptor constituting the toner transfer section, unevenness inevitably occurs in the layer thickness of the toner 4 located in the toner transfer section, which causes the toner 4 to be formed on the recording medium. There was a drawback that the quality of the recorded data deteriorated.

Therefore, an object of the present invention is to smoothly convey toner to a toner transfer section, eliminate unevenness in the thickness of the toner layer located on the toner transfer section, and improve the quality of recording formed on a recording medium. It is something.

[Means for Solving the Problem] A feature of the present invention is that magnetic toner is applied along the surface of the toner transporting member to the transparent support side of the toner transporting member, which includes a photoreceptor consisting of a transparent support, a transparent electrode, and a photoconductive layer. First and second magnet members each having a large number of magnetic poles for transporting the toner are rotatably arranged opposite to each other with a gap through which light can enter, and the toner is placed near each of the two magnet members. First and second toner containers are provided close to the conveyor, and the photoreceptor is located closer to the first magnet member than the intermediate position between the first and second magnet members. This is where a toner transfer section consisting of is provided.

[Function] The magnetic toner in the first toner container is transported on the toner transport body by the movement of the magnetic field caused by the rotation of the first magnet member, and the magnetic toner in the first toner container is transported on the toner transport body before reaching the center line P where the transport force decreases. The toner is conveyed onto a toner transfer section provided at a position offset toward the magnet member. At a position near the first magnet member on the toner transfer body that includes the toner transfer section, the magnetic field from the first magnet section is effectively acting, so that the toner is uniformly and unevenly distributed on the toner transfer section. Transported without. The toner conveyed onto the toner transfer section is transferred onto a recording medium via a toner transfer means by optically scanning a photoreceptor forming the toner transfer section from its transparent support side. The toner that has not been transferred is then further conveyed on the toner conveying body along the center line P to a position near the second magnet member, and further transferred to the second toner by the movement of the magnetic field caused by the rotation of the second magnet member. Collected in a container.

(Example) An example of the electrophotographic recording apparatus according to the present invention will be described based on the following aspects.

FIG. 3 shows a principle diagram of an electrophotographic recording apparatus according to the present invention. The photoreceptor 5 has a three-layer structure, in which a transparent electrode 5b is formed on the upper surface of a transparent support plate 5a made of glass or the like, and a photoconductive layer 5C is formed on the upper surface of this transparent electrode. Photoconductive layer 5
A recording medium 6 is conveyed facing the recording medium 6, and a transfer roller electrode connected to a power source E1 is disposed on the back side of the recording medium 6 as a transfer means 7. The charged toner 4 is conveyed on the surface of the photoconductive layer 5c of the photoreceptor 5, and in this example, the toner 4 is positively charged. A light beam modulated in accordance with, for example, image character information is applied to the toner transfer portion 8 of the photoreceptor 5, which is located opposite the transfer means 7 with the recording medium 6 in between, via the light scanning means 9, which is made of a polygon mirror or the like. 10
is scanned, the photoconductive layer 5c in the toner transfer section 8
The bright area that has been scanned is partially conductive, and the toner 4 in the bright area is charged with the opposite polarity to the toner in the dark area by the transparent electrode 5b, which is biased to a negative voltage by the power source E2, to the photoconductive layer. It is injected through the bright part of 5c. In the bright area, an electrostatic force is applied from the transfer means 7 to the toner 4 injected with charges of opposite polarity, and the toner is transferred onto the recording medium 6. That is, the photoreceptor 5 is exposed to light without being pre-charged, and the toner 4 is directly transferred to the recording medium 6.

FIG. 1 shows an embodiment of an electrophotographic recording apparatus based on the above principle of the present invention.

The first and second magnetic members 1 and 2 are separated by a predetermined gap d.
They are arranged opposite to each other.

This gap d is set so that light can enter therein, and at the same time, it is set to a size that prevents magnetic interaction between the two magnet members. In this example, the magnet member 1.degree. 2 is a magnet roller, which has a large number of N and S magnetic poles alternately magnetized in the circumferential direction, and conveys the toner by its rotation.

The magnetic members 1 and 2 are rotatably fitted into first and second cylindrical sleeves 11.12, respectively, and the sleeves 11.12 are connected by a toner conveying body 3. Further, in this example, the sleeves 11, 12 and the toner conveying body 3 are constructed as roller bodies made of non-magnetic material. Further, the toner transport body 3 has a photoreceptor 5.
is located at a position offset in the anti-toner transport direction from a position equidistant from both magnet members 1 and 2, preferably near the magnet member 1 as in this embodiment, and a toner transfer portion 8 is formed. As can be seen from FIG. 2, the photoreceptor 5 has a three-layer structure consisting of a transparent support 5a, a transparent electrode 5b, and a photoconductive layer 5c, as shown in the principle diagram in FIG. It is biased to a negative voltage by the power source E1. to .

Toner containers 13 and 14 for containing the toner 4 are disposed near both ends of the toner conveyor 3 and opposite the sleeves 11 and 12. The toner container 13 is provided with a doctor blade 13a connected to a power source E3 at the outlet of the toner 4. The dokuda blade 13a adjusts the layer thickness of the toner 4 to, for example, several tens of microns and injects charge, thereby positively charging the toner in this example. A recording medium 6 such as a recording paper or a recording film is conveyed facing the photoconductive layer 5c, and a transfer means 7 such as a transfer roller biased to a positive potential by a power source E2 is disposed on the back side of the recording medium 6. It is. The light beam 10 modulated according to the image character information enters the gap d by an optical scanning means 9 such as a rotating polygon mirror, and is optically scanned from the transparent support 5a side of the photoreceptor 5.

The toner 4 is conveyed from the toner container 13 on the right side toward the toner container 14 on the left side. That is, when the magnet members 1 and 2 are rotated clockwise, the toner container 1
The toner 4 in the toner 3 forms a toner chain on the first sleeve 11 on which the magnetic field of the magnet member 1 is effectively acting, and is conveyed from right to left while rotating. The toner chains are conveyed from the first sleeve 11 onto the photoconductive layer 5c of the toner transfer section 8 consisting of the photoreceptor 5 of the toner carrier 3. Toner transfer section 8
is located near the magnet member 1 where the magnetic field of the magnet member 1 effectively acts, so the toner is transferred to the photoconductive layer 5.
It is conveyed evenly over the surface of C with a constant layer thickness. While the toner is moving on the toner transfer section 8, the light beam 10 is caused by the optical scanning means 9 to enter the gap d between the two magnet members 1 and 2, and move the transparent support 5a perpendicularly to the conveyance direction of the recording medium 6. When light is scanned in the direction in which the light is scanned, the bright areas of the photoconductive layer 5C that have been optically scanned become partially conductive, and the toner in the bright areas is combined with the toner in the dark areas that have not been scanned with light (
Charges of opposite polarity to the positive charge are injected from the transparent electrode 5b through the bright part of the photoconductive layer 5c. Coulomb force is then applied from the transfer means 7 to the toner (negatively charged) injected with charges of opposite polarity, and the toner 4 is transferred onto the recording medium 6. Here, since the toner 4 is evenly and uniformly positioned on the toner transfer portion, the quality of printing of characters and the like formed by the toner transferred onto the recording medium 6 is improved. Toner 4 that was not transferred on the toner transfer section 8
The toner is further conveyed through the intermediate region to the vicinity of the magnet member 2, and is sent into the toner container 11 and collected by the movement of the magnetic field due to the rotation of the magnet member 2.

Note that in FIGS. 1 and 2, substantially the same members as in FIGS. 3 and 4 are given the same reference numerals.

Further, in this embodiment, the toner conveying body 3 and the sleeves 11 and 12 are integrally formed, but they may be formed as separate members, and the magnetic members are each made of a magnet instead of the magnetic rollers 1 and 2. The belt may be rotatably arranged.

[Effects of the Invention] Since the present invention has the above-described configuration, the toner transported on the toner transport body is moved along the center line P where its transport force decreases.
Before reaching the top, the toner is smoothly and evenly conveyed onto a toner transfer portion provided on the first magnetic member band on a toner conveying member on which the magnetic field of the first magnetic member effectively acts.

Therefore, when the toner is transferred to the recording medium, the toner is positioned uniformly and evenly on the toner transfer area,
The quality of recordings formed on the recording medium is significantly improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of one embodiment of the present invention, FIG. 2 is an enlarged view of the main part of FIG. FIG. 3 is a cross-sectional view for explaining a problem. 1.2... Magnet member, 3... Toner transport body, 4...φ toner, 5...
Photoreceptor, 6... Recording medium, 7... Transfer means, 8
. . . Toner transfer unit, 9 . . Optical scanning means, 10 .
- Light, 13.14... Toner container, d... Gap. that's all

Claims (1)

[Scope of Claims] A toner transporting body including a photoconductor consisting of a transparent support, a transparent electrode, and a photoconductive layer has a large number of magnetic poles on the side of the transparent support for transporting magnetic toner along the surface of the toner transporting body. first and second magnetic members having a structure are rotatably disposed opposite to each other with a gap through which light can enter, and a first and a second magnetic member having a magnet member are disposed in a rotatable manner to face each other with a gap through which light can enter; First and second toner containers are provided respectively, and a toner container configured by the photoreceptor is located at a position closer to the first magnet member than an intermediate position between the first and second magnet members. A transfer section is provided, and a light scanning means for scanning light from the gap to the toner transfer section is provided on the transparent support side of the toner transport body, and is located on the surface of the photoconductive layer of the toner transfer section. Electrophotography, characterized in that it is provided with a transfer means that faces the above-mentioned toner via a recording medium and transfers the toner located in a bright area subjected to optical scanning on the surface of the photoconductive layer to the above-mentioned recording medium. Recording device.