JPH11231602A - Image forming device - Google Patents

Abstract

(57) [Problem] To provide an image forming apparatus in which toner does not spill on a toner image carrier. SOLUTION: A toner image carried on a toner image carrier 1 stretched by a plurality of rollers in a direction perpendicular to the transport direction of the printing paper 5 is transferred by a transfer facing roller 4 in a direction perpendicular to the transport direction of the printing paper 5. An image forming apparatus of an orthogonal transfer system for transferring the toner image transferred to the printing paper 5 and fixing the toner image transferred to the printing paper 5 in an area where the surface of the toner image carrier 1 faces downward, The developing roller 11 of the developing means 7 develops the toner image carrier 1 in an area where the running of the roller 4 is not hindered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an orthogonal transfer type image forming apparatus which prevents toner from spilling onto a toner image carrier.

[0002]

2. Description of the Related Art In recent years, toner-type image forming apparatuses capable of forming clear images with excellent resolution, such as laser printers, have become widespread. Among such toner-type image forming apparatuses, Japanese Patent Application No. 7-328600.
As described above, the orthogonal transfer type image forming apparatus that moves the toner image carrier in a direction orthogonal to the transport direction of the printing paper and transfers the toner image in small steps at a time is a small-sized product due to its configuration. It is very suitable for promoting the conversion.

[0003] A conventional image forming apparatus which is compatible with color by the orthogonal transfer system will be described below.

FIG. 17 is a schematic configuration diagram of a conventional image forming apparatus, and FIG. 18 is a perspective view showing a transfer process of the conventional image forming apparatus. FIG. 19 is a schematic view showing a state of forming a toner layer of a developing roller of a conventional image forming apparatus.
FIG. 20 is a schematic diagram showing a state of toner dropped from a developing roller of a conventional image forming apparatus.

In FIG. 17 and FIG. 18, a toner image carrier 1 composed of a photoreceptor belt whose surface is coated with a layer of an organic photoconductive material comprises a support roller 2, which is also a driving roller, a displacement roller 3, and a transfer opposing roller. The printing paper 5 is stretched in a direction perpendicular to the conveying direction of the printing paper 5 by a plurality of rollers such as 4, and rotates in the direction of an arrow at the time of image formation to form a toner image on the surface of the toner image carrier 1. Around the toner image carrier 1, charging means 6, developing means 7, cleaning means 8, static elimination means 9 and the like are arranged, and an upper portion of the toner image carrier 1 is exposed to laser light. Means 10 are arranged. The devices around the toner image carrier 1 are all installed above the toner image carrier 1 so as not to hinder the movement of the transfer opposing roller 4. As shown by the arrow in FIG. 17, when the toner image carrier 1 rotates in a direction orthogonal to the transport direction of the printing paper 5, the portion passing through the charging means 6 is uniformly charged to about -600V. Exposure means 10 irradiates the surface of toner image carrier 1 with laser light corresponding to the four primary colors on the surface of toner image carrier 1 based on the image signals of the four primary colors of cyan, magenta, yellow, and black. The potential of the part irradiated with the laser light is -10
By increasing the voltage to about 0 V, electrostatic latent images divided into four for each primary color are simultaneously formed on the surface of the toner image carrier 1. When the four primary colors of toner are pressed against the portion where the electrostatic latent image is formed by the developing roller 11, the toner of each of the four primary colors becomes a visible image on the toner image carrier 1 by toner particles having a negative polarity. Images appear one after another.

[0006] As shown in FIGS.
Is composed of four parts for each primary color.
C is cyan, developing means 7M is magenta, developing means 7Y is yellow, and developing means 7B is black. Are formed on the developing roller 11 of each of the four primary colors.
As shown in FIG. 19, the developing roller 11 has toner layers 1 of four colors of cyan, magenta, yellow, and black from the right.
2 are formed, and each toner layer 12 is separated by a gap 13 or a gap 14 to prevent color mixing. However, since these gaps 13 and 14 are sealed by sealing materials 15 and 16, The toner does not adhere.

The feature of such an orthogonal transfer type image forming apparatus is that, as shown in FIG. 18, during the transfer, the rotation of the toner image carrier 1 and the conveyance of the printing paper 5 are temporarily stopped, and the transfer plate 17 is stopped. (See also FIG. 17) The toner image carrier 1 is displaced by being rubbed (rubbed) with the movement of the transfer opposing roller 4 on the printing paper 5 that is stationary above. At this time, the displacement roller 3 is used to prevent the toner image carrier 1 from sagging.
Is displaced following the movement of the transfer opposing roller 4. In this conventional example, the transfer end surface of the toner image carrier 1 that has been transferred to the printing paper 5 is successively separated from the printing paper 5, and is in contact with the printing paper 5 by the transfer opposing roller 4. Only the part being transferred is attached.

[0008] During the transfer step, the printing paper 5
If the printing paper 5 is not lifted from the transfer plate 17 and the slippage of the printing paper 5 is not prevented, there is a possibility that a printing shift occurs. Therefore, in order to suppress the occurrence of printing deviation, a positive voltage having a polarity opposite to that of the toner image is applied to the transfer plate 17 so that a positive charge is applied. Then, the printing paper 5 is electrostatically attracted by the static electricity generated on the surface of the transfer plate 17 and temporarily bound on the transfer plate 17. Then, the transfer plate 17 having a positive charge attracts the negatively charged toner images of the four primary colors from the surface of the toner image carrier 1 to be peeled off and transferred to the printing paper 5.

Whenever the transfer for one process is completed, the transfer opposing roller 4 passes over the printing paper 5 and moves out of the area of the printing paper 5, so that the toner image carrier 1 is separated from the printing paper 5. . Immediately before the toner image carrier 1 is separated from the printing paper 5, the application of the voltage to the transfer plate 17 has already been stopped, so the printing paper 5 electrostatically attracted to the transfer plate 17 is released from the suction. I have. The transport of the printing paper 5 is started in order to proceed to the next transfer step, and the transporting distance of the printing paper 5 is only the width of the developing area of each color of the toner image carrier 1 shown in FIG. The print paper 5 is intermittently sent to the fixing means 18 by the width of the development area of each color.
When the printing paper 5 on which the image has been transferred is conveyed and placed on the support member 19, the fixing means 18 of the hot air fixing system for performing the fixing without contacting the printing paper 5 has a heat source and a blower fan inside. Hot air is generated by the hot air means 20 and blown onto the printing paper 5 so that the toner particles on the surface of the printing paper 5 are melted and fixed on the printing paper 5.

[0010]

However, in the above-described conventional image forming apparatus, as shown in FIG.
The outer diameter of the developing roller 11 is the same over the entire length. Therefore, even if the gaps 13 and 14 are formed by sealing the gaps 13 and 14 between the toner layers 12 of the developing roller 11 with the sealing materials 15 and 16, the sealing is not performed over the entire circumference of the developing roller 11. The toner spilled from the toner may accumulate in the gaps 13 and 14. As shown in FIG. 17, when the developing area on the toner image carrier 1 is developed by the developing roller 11, the surface of the toner image carrier 1 faces upward so as not to hinder the movement of the transfer opposing roller 4. Within the region. In other words, since the toner image carrier 1 is located below the developing roller 11, when sudden toner leakage occurs from the gaps 13 and 14 of the developing roller 11, as shown in FIG. The toner spills onto the carrier 1 and becomes a drop of toner, thereby contaminating the toner image carrier 1. Then, at the time of transfer to the printing paper 5, finally, toner color mixture and dirt are generated by the dropped toner,
There was a problem that the sharpness of the image was lost.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide an image forming apparatus in which toner does not fall onto a toner image carrier.

[0012]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention provides a method for transferring a toner image carried on a toner image carrier stretched by a plurality of rollers in a direction perpendicular to a conveying direction of a printing paper. An orthogonal transfer type image forming apparatus in which a toner image transferred onto a printing paper is fixed by transferring the toner image onto the printing paper in a direction perpendicular to the conveying direction of the printing paper by an opposing roller, and the surface of the toner image carrier faces downward. And the developing roller of the developing means develops the toner image carrier in an area that does not hinder the movement of the transfer opposing roller.

According to the present invention, it is possible to provide an image forming apparatus in which toner does not drop onto a toner image carrier.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a toner image carried on a toner image carrier stretched by a plurality of rollers in a direction perpendicular to a conveying direction of a printing paper is transferred and opposed. This is an orthogonal transfer type image forming apparatus in which a toner image transferred to a printing paper is fixed by transferring the toner image onto the printing paper in a direction orthogonal to a conveying direction of the printing paper by a roller, and a surface of the toner image carrier faces downward. The developing roller of the developing means develops the toner image carrier in the area that does not hinder the movement of the transfer opposing roller, and the toner does not drop onto the toner image carrier. Having.

According to a second aspect of the present invention, in the first aspect of the present invention, the toner image carrier is formed of a photoreceptor belt, and is provided with exposure means for exposing the toner image carrier based on an image signal. It has the function of preventing the toner from spilling onto the toner image carrier.

According to a third aspect of the present invention, in the second aspect of the invention, the developing means is configured to develop only a single color, so that the toner does not fall onto the toner image carrier. Has an action.

According to a fourth aspect of the present invention, in the second aspect of the invention, the developing means comprises cyan, magenta,
The toner is developed using the three primary colors of yellow, and has the effect of preventing the toner from falling onto the toner image carrier.

According to a fifth aspect of the present invention, in the second aspect, the developing means comprises at least cyan,
The development is performed using the four primary colors of magenta, yellow, and black, and has the effect of preventing the toner from falling onto the toner image carrier.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
As will be described with reference to FIG. 16, the same parts as those in the conventional example are denoted by the same reference numerals.

(Embodiment 1) The outline of one embodiment of the present invention is that, in order to prevent falling toner from adhering to the surface of the toner image carrier, the toner is placed above the developing roller so that the falling toner is not generated anyway. What is necessary is just a toner image carrier. Therefore, the belt-shaped toner image carrier has an area where the surface faces upward, an area where the surface is vertical, and an area where the surface faces downward. In such a manner that the developing roller of the developing means develops the toner image carrier in a region which does not hinder the traveling of the toner image carrier.

Hereinafter, a color-compatible image forming apparatus will be described in detail with reference to FIGS. 1 to 16 as an embodiment of the present invention.

FIG. 1 is a schematic configuration diagram of an image forming apparatus according to one embodiment of the present invention, and FIG. 2 is a perspective view showing a transfer process of the image forming apparatus according to one embodiment of the present invention. FIGS. 3 and 4 are schematic views showing the formation state of the toner layer of the developing roller of the image forming apparatus according to the embodiment of the present invention, and FIG. 5 is a developing unit of the image forming apparatus according to the embodiment of the present invention. FIG. 4 is a schematic diagram illustrating a correspondence between the image forming apparatus and a toner image carrier. 6 to 8 are schematic views showing a transfer process in an outward path of the image forming apparatus according to one embodiment of the present invention.
FIG. 11 to FIG. 11 are schematic views showing a tracing step on the return path of the image forming apparatus according to the embodiment of the present invention. FIGS. 12 to 15 are schematic diagrams showing a transfer state of the image forming apparatus according to one embodiment of the present invention, and FIG. 16 is a schematic diagram of a fixing unit of the image forming apparatus according to one embodiment of the present invention. is there.

1 and 2, a toner image carrier 1 composed of a photoreceptor belt whose surface is coated with a layer of an organic photoconductive material comprises a plurality of support rollers 2, displacement rollers 3, transfer opposing rollers 4, and the like. Are stretched in a direction orthogonal to the transport direction of the printing paper 5. At the time of image formation, which is a stage prior to the transfer step, a toner image is formed on the surface of the toner image carrier 1 by rotating in the direction of the arrow opposite to the conventional example. Around the toner image carrier 1, a charging unit 6, a developing unit 7, a cleaning unit 8, and a discharging unit 9
An exposure unit 10 for irradiating a laser beam is disposed above the toner image carrier 1. In an embodiment of the present invention, a case where a laser is used as a typical example of the exposure unit 10 will be described.
The exposure means 10 is not limited to a laser, but may be an LED or LC.
D may be used.

Most of the devices around the toner image carrier 1 are arranged on the upper side of the toner image carrier 1 as in the conventional example. In order to eliminate this, only the developing means 7 is arranged below the toner image carrier 1. Of course, the arrangement of the developing means 7 is designed so as not to hinder the movement of the transfer opposing roller 4.

As shown by the arrow in FIG. 1, when the toner image carrier 1 rotates in a direction perpendicular to the direction in which the printing paper 5 is conveyed, the portion passing through the charging means 6 is uniformly charged to about -600V. Exposure means 10 irradiates the surface of toner image carrier 1 with laser light corresponding to the four primary colors on the surface of toner image carrier 1 based on the image signals of the four primary colors of cyan, magenta, yellow, and black. When the potential of the portion irradiated with the laser beam rises to about −100 V, an electrostatic latent image divided into four for each primary color is simultaneously formed on the surface of the toner image carrier 1. When the developing device 7 disposed below the toner image carrier 1 presses the four primary colors of toner on the portion where the electrostatic latent image is formed with the developing roller 11, a visible image is formed on the toner image carrier 1. The toner images of each of the four primary colors appear one after another.

More specifically, as shown in FIG. 3, the development of the four primary colors is performed simultaneously by the four primary color toner layers 12 formed on the common developing roller 11 by dividing the primary colors into four. At the time of development, the developing means 7 causes the developing roller 11 to which the negatively charged toners of the four primary colors adhere to the toner image carrier 1 in order to make the respective electrostatic latent images corresponding to the four primary colors visible. To transfer the toners of the four primary colors to the portions of the electrostatic latent image divided into the four primary colors on the surface of the toner image carrier 1 so that the toner images of the four primary colors of cyan, magenta, yellow, and black are It is formed in a state divided into.

As shown in FIGS. 1 and 2, the developing means 7 comprises four parts for each primary color. The developing means 7C is cyan, the developing means 7M is magenta, the developing means 7Y is yellow, and the developing means 7B The toner layers of the four primary colors of cyan, magenta, yellow, and black are formed on the common developing roller 11 so as to be divided into four for each of the primary colors by using the primary color toners contained therein. As shown in FIG. 3, a toner layer 12 of four colors of cyan, magenta, yellow, and black is formed on the developing roller 11 from the right, and each toner layer 12 has a gap 13 for preventing color mixing.
Alternatively, it is separated by the gap 14, but this gap 13,
The portion 14 is sealed by the sealing materials 15 and 16, so that the toner does not normally adhere thereto.

FIG. 3 shows an example of the color developing roller 11 according to claim 5. In order to reproduce a color tone of a photograph or the like, light cyan or light magenta is added in addition to the four primary colors. Is also good. Although not shown, a description will be given of “claim 4”. Since the black color tone itself can be synthesized with the three primary colors of cyan, magenta, and yellow,
The developing roller 11 is formed by removing cyan, magenta,
It is also possible to use one for the three primary colors of yellow. Further, as shown in FIG. 4, the developing roller 11 itself may correspond to a single color such as black according to claim 3, but in this case, the gaps 14 at both ends of the single color toner layer 12 are
6 will seal.

The ratio of the width of the toner layer 12 for one color on the developing roller 11 to the width of the gap 13 is {1: 1},
{2: 1}, {3: 1}, etc. are conceivable, but the case of {1: 1} will be described in order to simplify the description.

Returning to FIG. 3, the developing roller 1 corresponding to the color
1 will be described. Clearances 13 and 14 of developing roller 11
Is sealed by the seal members 15 and 16 so that toner does not normally adhere thereto. However, the gap between the toner layer 12 of the developing roller 11 is sealed by the seal members 15 and 16. Even if the toner particles 13 and 14 are formed, the toner does not seal over the entire circumference of the developing roller 11.
May accumulate on 3,14. Although this point is the same as the conventional example, as shown in FIG. 5, in the present invention, since the developing roller 11 of the developing unit 7 is disposed below the toner image carrier 1, the toner is Since the toner does not fall on the surface 1, no falling toner itself occurs. FIG. 20 of a conventional example
5 is viewed from above the toner image carrier 1, FIG. 5 of the present invention is viewed from below the toner image carrier 1. FIG. Therefore, in the present invention, even if the toner suddenly leaks from the gaps 13 and 14 of the developing roller 11, the toner falls toward the front in the drawing, so that the toner adheres to the toner image carrier 1 on the other side. There is no.

According to the first aspect, it is not necessary to dispose the entire developing means 7 below the toner image carrier 1, and at least the developing roller 11 is provided in a region where the surface of the toner image carrier 1 faces downward. Since it only needs to be placed in
Part of the developing means 7 may be arranged at a position where the surface of the toner image carrier 1 does not face downward. That is, the belt-shaped toner image carrier 1 has an area where the surface is upward, an area where the surface is vertical, and an area where the surface is downward, but in any case, the developing roller 11 has the surface of the toner image carrier 1 facing downward. It is sufficient that the developing means 7 is arranged at a position where development can be performed in the area, and it does not matter where the other parts of the developing means 7 are arranged. Of course, the developing means 7 needs to be arranged at a position which does not hinder the movement of the transfer opposing roller 4.

The movement of the transfer opposing roller 4 and the displacement roller 3 will be described for a while. As shown in FIG. 1, the support roller 2 is also a driving roller for rotating the toner image carrier 1, but the support roller 2 is a roller that rotates at a fixed position without its rotating shaft moving. On the other hand, the displacement roller 3 and the transfer opposing roller 4 are movable rollers whose rotating shafts move, and the displacement roller 3 and the transfer opposing roller 4 are used to keep the tension of the loop of the toner image carrier 1 that is deformed as the transfer opposing roller 4 runs. 3 is displaced left and right. FIG. 1 shows a state in which the toner image is moved onto the printing paper 5 after the development is completed.

In the transfer step shown in FIG. 2, the transfer opposing roller 4 runs on the printing paper 5 while pressing the toner image carrier 1 from behind. However, unlike the conventional example, the transfer end surface of the toner image carrier 1 is not separated from the surface of the printing paper 5. This will be described in more detail with reference to FIGS. In the outward path shown in FIGS. 6 to 8, as shown in FIG. 6, the transfer opposing roller 4 comes down to the printing paper 5 side as indicated by the dashed arrow, and the transfer starts. As shown in FIGS. 7 and 8, the transfer opposing roller 4 travels from left to right on the printing paper 5 to transfer the toner image to the printing paper 5, but as shown in FIG. Even when the transfer is completed, the transfer end surface of the toner image carrier 1 is not separated from the surface of the printing paper 5. However, in the return path shown in FIGS. 9 to 11, as shown in FIGS. 9 and 10, the transfer opposing roller 4 travels from the right to the left on the return path so as to trace over the print paper 5 on which the toner image has been transferred once. Then, the transfer end surface of the toner image carrier 1 starts to gradually separate from the surface of the printing paper 5 with the return of the transfer opposing roller 4. FIG. 10 shows a state in which the transfer opposing roller 4 has finished tracing on the printing paper 5 in the return path and is about to float from the printing paper 5. Thereafter, the transfer opposing roller 4 floats from the printing paper 5, and as shown in FIG.
And is stored in the loop of the toner image carrier 1 formed.

In this way, the transfer paper 4 is transferred onto the printing paper 5 once transferred in the forward path of the transfer paper roller 4.
The reason why the vehicle travels along the return path is to improve the transfer rate of the toner image from the toner image carrier 1 to the printing paper 5 (the adhesion rate of the toner image to the printing paper 5). For example, assuming that the transfer rate is 90% on the outward path, tracing on the return path can improve the transfer rate by 5% to 95%.
% Can be reached. This makes it possible to keep the density of the toner image transferred to the printing paper 5 unchanged even if the toner image is saved by slightly reducing the thickness of the toner image in the development stage. Of course, if it is not necessary to conserve toner, the transfer opposing roller 4 may float back from the print sheet 5 and return so as not to trace on the print sheet 5 in the return path.

At the time of transfer to the printing paper 5, as shown in FIG.
7 (see also FIG. 1) while the printing paper 5 is stationary.
The rotation of the toner image carrier 1 is also stopped. Then, the portion of the toner image carrier 1 on which the four primary color toner images are formed is rubbed against the printing paper 5 by moving the transfer opposing roller 4 from the back side on the forward path and the return path, thereby transferring the four primary color toner images.

During the transfer process, the printing paper 5
If the printing paper 5 is not lifted from the transfer plate 17 and the slippage of the printing paper 5 is not prevented, there is a possibility that a printing shift occurs. Therefore, in order to suppress the occurrence of printing deviation, a positive voltage having a polarity opposite to that of the toner image is applied to the transfer plate 17 so that a positive charge is applied. Then, the printing paper 5 is electrostatically attracted by the static electricity generated on the surface of the transfer plate 17 and temporarily bound on the transfer plate 17. Then, the transfer plate 17 having a positive charge attracts the negatively charged toner images of the four primary colors from the surface of the toner image carrier 1 to be peeled off and transferred to the printing paper 5.

When the transfer opposing roller 4 reciprocates on the printing paper 5 and the transfer for one process is completed, and the transfer opposing roller 4 is stored in the loop of the toner image carrier 1, the toner image carrier 1 Is separated from the printing paper 5. At this time, the transfer opposing roller 4 has already moved out of the area of the printing paper 5. Immediately before the toner image carrier 1 is separated from the printing paper 5, the application of the voltage to the transfer plate 17 has already been stopped, so the printing paper 5 electrostatically attracted to the transfer plate 17 is released from the suction. I have. The conveyance of the printing paper 5 is started in order to proceed to the next transfer step, and the conveyance distance of the printing paper 5 is only the width of the developing area of each color of the toner image carrier 1 shown in FIG.

While the printing paper 5 is being conveyed, as shown in FIG. 1, the cleaning means 8 removes residual toner on the surface of the toner image carrier 1 with a cleaning blade or a cleaning brush to generate waste toner. The collected toner image carrier 1 is physically cleaned. Then, the charge removing means 9 is provided for the toner image carrier 1 after removing the residual toner.
The surface of the toner image carrier 1 is electrically cleaned by neutralizing the negative charges remaining on the surface of the toner image carrier 1. Then, exposure and development are performed on the surface of the cleaned toner image carrier 1 to form a new toner image. Note that the installation of the charge removing means 9 is not an essential requirement.

As shown in FIGS. 12 to 15, the toner image carrier 1 has a developing area for each color developed by the developing means 7 and a non-developing area sandwiched between the developing areas. The width of the development area in the transport direction of No. 5 is set to be the same for each color. In particular, in FIGS. 12 to 15, the width of the development area and the width of the non-development area are set to {1: 1}.
Hereinafter, a method of forming a color toner image will be described.

The method of forming a color toner image starts from the state shown in FIG. 12, but in the first transfer, only a {cyan} toner image is transferred in one step.
In the column, only the cyan toner image is transferred. When the printing paper 5 is conveyed by the width of the development area, the second transfer is performed. However, even in the second transfer, only the cyan image is transferred in one process, so that the cyan in the second column is also transferred. Is transferred.

Next, as shown in FIG. 13, in the third transfer, the {cyan, magenta} toner image is transferred in one step, so the {cyan, magenta} toner image is superimposed on the first column. In the third column, only the {cyan} toner image is transferred. When the printing paper 5 is transported by the width of the developing area,
Similarly, the fourth transfer is performed. Even in the fourth transfer, the {cyan, magenta} toner image is transferred in one process, so the {cyan, magenta} toner image is superimposed on the second column. In the fourth row, only the {cyan} toner image is transferred.

Next, as shown in FIG. 14, in the fifth transfer, a {cyan, magenta, yellow} toner image is transferred in one step, so that the {cyan, magenta, yellow} toner image is in the first column. In the third column, a {cyan, magenta} toner image is superimposed. In the fifth column, only the {cyan} toner image is transferred. When the printing paper 5 is conveyed by the width of the development area, the sixth transfer is performed in the same manner. Even in the sixth transfer, {Cyan, Magenta, Yellow} is performed in one process.
, The second column overlaps the cyan, magenta and yellow toner images, the fourth column overlaps the cyan and magenta toner images, and the sixth column overlaps the cyan image. Is transferred.

After that, as shown in FIG. 15, in the seventh transfer, the toner image of {cyan, magenta, yellow, black} is transferred in one process, so the first column is {cyan, magenta, yellow, black}. A color toner image is formed by the toner images of
A yellow toner image is superimposed. In the fifth column, the {cyan, magenta} toner image is superimposed, but in the seventh column, only the {cyan} toner image is transferred.

At the end of the transcription, the reverse path is just followed.
In the process, cyan, magenta, yellow, and black toner images were transferred, but cyan was missing, and magenta, yellow, and black were lost, and magenta was missing, resulting in yellow and black. Is only black.

After the above steps are repeated, as shown in FIG. 2, the printing paper 5 is intermittently sent to the fixing means 18 by the width of the developing area of each color. And printing paper 5
The fixing means 18 of the hot air fixing system for performing the fixing without contact with the
When the printing paper 5 on which the image has been transferred is conveyed and placed on the support member 19 of the fixing means 18, the hot air means 20 having a heat source 21 and a blowing fan 22 therein is constructed as shown in FIG. To generate hot air.

The air flow generated by the blower fan 22 is blown against the heat transfer member 23 heated by the heat source 21 and flows into the heat transfer member 23 from the uppermost through hole 24. When flowing out of the through hole 24 of the uppermost layer, the air flow takes in heat from the periphery of the through hole 24 and diffuses when flowing out of the through hole 24 of the same uppermost layer, and successively transfers heat from each layer of the heat transfer member 23. The printing paper 5 is robbed and becomes hot air, blows out from the lowermost through-hole 24 and sprays on the printing paper 5, melts the toner particles on the surface of the printing paper 5, and fixes it on the printing paper 5.

Finally, to briefly describe what is related to the "claim 2", the toner image carrier does not always need to use a photosensitive member, and sometimes does not need an exposure unit. This is because a toner image can be formed by forming an electrostatic latent image with a heat source and developing it, or by blowing off a solid-coated toner image carrier with an air jet, as if carving a print. This is because a toner image can also be formed.

[0048]

As described above, according to the present invention, a toner image carried on a toner image carrier stretched by a plurality of rollers in a direction orthogonal to the transport direction of the printing paper is transferred to the printing paper by a transfer opposing roller. An image forming apparatus of an orthogonal transfer system for transferring the toner image transferred to the printing paper in a direction orthogonal to the transport direction of the toner and fixing the toner image transferred to the printing paper, in a region where the surface of the toner image carrier faces downward. In addition, the developing roller of the developing means develops the toner image carrier in a region where the movement of the transfer opposing roller is not hindered. Therefore, it is possible to avoid the color mixture and contamination of the toner, thereby maintaining the sharpness of the image.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a transfer process of the image forming apparatus according to the embodiment of the present invention;

FIG. 3 is a schematic diagram showing a state of forming a toner layer of a developing roller of the image forming apparatus according to the embodiment of the present invention;

FIG. 4 is a schematic view showing a state of forming a toner layer of a developing roller of the image forming apparatus according to the embodiment of the present invention;

FIG. 5 is a schematic diagram showing correspondence between a developing unit and a toner image carrier of the image forming apparatus according to the embodiment of the present invention;

FIG. 6 is a schematic diagram showing a transfer process in an outward path of the image forming apparatus according to the embodiment of the present invention;

FIG. 7 is a schematic diagram showing a transfer process in an outward path of the image forming apparatus according to the embodiment of the present invention;

FIG. 8 is a schematic diagram showing a transfer process in an outward path of the image forming apparatus according to the embodiment of the present invention;

FIG. 9 is a schematic view showing a tracing step in the return path of the image forming apparatus according to the embodiment of the present invention;

FIG. 10 is a schematic view showing a tracing process on the return path of the image forming apparatus according to the embodiment of the present invention;

FIG. 11 is a schematic view showing a tracing step in the return path of the image forming apparatus according to the embodiment of the present invention;

FIG. 12 is a schematic diagram showing a transfer state of the image forming apparatus according to the embodiment of the present invention;

FIG. 13 is a schematic diagram showing a transfer state of the image forming apparatus according to the embodiment of the present invention;

FIG. 14 is a schematic diagram showing a transfer state of the image forming apparatus according to the embodiment of the present invention;

FIG. 15 is a schematic diagram illustrating a transfer state of the image forming apparatus according to the embodiment of the present invention;

FIG. 16 is a schematic diagram of a fixing unit of the image forming apparatus according to the embodiment of the present invention.

FIG. 17 is a schematic configuration diagram of a conventional image forming apparatus.

FIG. 18 is a perspective view illustrating a transfer process of a conventional image forming apparatus.

FIG. 19 is a schematic view illustrating a state of forming a toner layer of a developing roller of a conventional image forming apparatus.

FIG. 20 is a schematic diagram illustrating a state of toner dropped from a developing roller of a conventional image forming apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 toner image carrier 2 support roller 3 displacement roller 4 transfer opposing roller 5 printing paper 6 charging means 7 developing means 7C developing means 7M developing means 7Y developing means 7B developing means 8 cleaning means 9 discharging means 10 exposure means 11 developing roller 12 toner Layer 13 Gap 14 Gap 15 Seal material 16 Seal material 17 Transfer plate 18 Fixing means 19 Support member 20 Hot air means 21 Heat source 22 Blow fan 23 Heat transfer member 24 Through hole

Claims (5)

[Claims] A transfer roller configured to transfer a toner image carried on a toner image carrier stretched by a plurality of rollers in a direction perpendicular to a transport direction of the print paper in a direction perpendicular to the transport direction of the print paper by a transfer opposing roller; An image forming apparatus of an orthogonal transfer system for transferring the toner image transferred to the printing paper and fixing the toner image onto the printing paper, wherein the toner image carrier is in an area where the surface of the toner image carrier faces downward and does not hinder the movement of the transfer opposing roller. An image forming apparatus, wherein a developing roller of a developing unit develops a toner image carrier in an area. 2. A toner image bearing member comprising a photosensitive belt,
2. The image forming apparatus according to claim 1, further comprising an exposure unit that exposes the toner image carrier based on the image signal. 3. An image forming apparatus according to claim 2, wherein said developing means develops only a single color. 4. An image forming apparatus according to claim 2, wherein said developing means develops using three primary colors of cyan, magenta and yellow. 5. The developing means comprises at least cyan, magenta,
3. The image forming apparatus according to claim 2, wherein development is performed using four primary colors of yellow and black.